Trione-Annadel State Park

A beautiful chunk of Sonoma County! Established as a state park in 1971, Annadel has a surprisingly rich and layered history. Long before it became a park, the land was home to Wappo and Pomo peoples, who lived and traveled through this area for centuries. In the 19th century, the property was purchased by William Hood, a Scottish immigrant, and over time it passed through several owners. Fast forward to the 1960s and ’70s, when philanthropists Henry Trione and Joseph “Joe” Long stepped in and helped preserve the land, contributing millions to ensure it would be protected as public open space. Thanks to that effort, this remarkable area was saved from development and is now open for everyone to enjoy. Today, Trione-Annadel State Park spans just over 5,000 acres of rolling hills, oak woodlands, meadows, and volcanic rock formations. It’s a favorite spot for hikers, mountain bikers, and runners, all sharing a network of well-maintained trails. If it’s your first visit, starting with a route that takes you to and around Lake Ilsanjo is a great idea. It’s a peaceful and scenic area that gives you a good feel for the park without being too demanding. Whether you’re looking for a casual walk or a longer outing, Annadel is one of those places that reminds you how lucky Sonoma County is to have such easy access to open space.

We had such an amazing hike here that I hesitate to talk about it. We have hiked all over California and the West, and were delighted to find this beautiful and serene place. There are miles of trails, some very rocky, so care is required going up and down. We saw quite a few mountain bikers, (mostly middle aged men) not the speed demons of Mt. Tamalpais. The park is utterly quiet, with gorgeous meadows and somber oak trees. I was sitting on a small boulder at one point and the thought came to me that I might be in heaven. Serendipity at its lovely best.

Trione-Annadel State Park is a true gem for outdoor enthusiasts. The park features miles of well-maintained trails perfect for hiking, biking, and horseback riding, all set against stunning natural scenery. Wildflowers, woodlands, and lakes create a beautiful and peaceful environment, ideal for both adventure and relaxation. The park is clean, safe, and offers plenty of picnic spots and wildlife viewing opportunities. With its diverse landscapes and excellent facilities, Trione-Annadel State Park is a must-visit destination for nature lovers.

Great trails for hiking, biking or horseback riding. No dogs though. A mix of single track & fire gravel roads. Can be rocky. Mixed terrain w/ beautiful views, a lake, flowers, birds & creeks. Beware of the poisen oak! Simply, nature at it's best👍

I love that we have so many hiking trails in Sonoma County to explore. There are a variety of trails to hike. A variety of landscaping is offered from for trees, a lake, ferns & creeks.

NO DOGS ALLOWED. Please be respectful of this for health of wildlife and ecosystem. Lovely hike through oak woodlands and a variety of wildflowers. So nice to see the tadpoles in the small pond. Various levels of difficulty of hiking, but definitely lots of uphill. Lots of exposure in the sun but some cover in the oak. Woodlands. No parking fee at Cobblestone trail.

This state park had incredible mountain bike trails! It was super awesome to ride. Would be even better if they had bathrooms with flushing toilets and running water, but otherwise a beautiful park to visit.

Stunning views and miles of trails! Great for a MTN bike ride, a trail run, or a hike. There's something fot everyone here. Some trails are definitely more technical than others, so plan accordingly. A wonderful trail network though and well maintained.

Fantastic gem right in our backyard. We spent many years mountain biking the numerous trails. Views are stunning as well as the beauty of the park. Try to hike weekly, very peaceful and good exercise. A beautiful park to get away from the hustle and bustle.

Another huge State Park in the vicinity-in Santa Rosa. We have done a couple of medium to hard trails and yet prefer the easy straight walk along the creek. There are houses too along that path. Lots of space for one to walk comfortably at one's own pace. We usually do 3.0 miles back and forth at a quick pace and feel well worked out. Enough tree cover, so good to walk on a sunny day too.

Beautiful park! Flora and fauna galore! So many trails! Lots of hills and meadows. I'm a starry eyed hiker!‍

Perfect park for horseback riding!!!!!! Or hiking. Lovely outdoor place to walk and relax --. Take a lunch. There are tables to eat and relax and enjoy the Park!!!! Beautiful and close by!!!!!

(Uhm...where's the "Trione"?) Officially this park is called "Trione-Annadel," but it appears everyone is shortening it, even Yelp. I'd never visited before, so I decided to do a hike from the northernmost trailhead. Being adjacent to the City of Santa Rosa, the park was much bigger than I expected. For instance, I completed a 11.3 mile loop here; but I only saw about half of the park. Being a weekday, I saw few people on my route, mostly mountain bikers. Unfortunately, as in most parks frequented by bikers, some of the trails were fairly torn-up. There was quite the mix of terrain at T-A Park. I started in a shady forest of mixed oak, madrone, and bay (with plenty of birdsong); moved to some hilltops with nice, rocky formations; then found myself in open, rolling grasslands dotted with large oaks. I passed by a large, reed-lined lake and eventually was hiking in shaded redwood forest. If I was local, I'm sure I would visit this outdoor resource often. As it is, I will have to satisfy myself with a second visit on some future road trip. Maybe then I can see the other half.

Annadel is my go to hiking spot in Santa Rosa. It's teaming with wildlife and there's a ton of trails of varying difficulty perfect for hiking, trail running, and mountain biking (know who has the right of way)! In the summer I love hiking up there with a tasty lunch and cooling off via a quick dip in Lake Ilsanjo (it's finally full again!) Beware of ticks and please practice leave no trace principles.

One of the most missed activities during the inital stage of the Covid 19 pandemic was hiking in Annadel It was so frustrating (but understandable) living within 200 yards of a trailhead and not being able to hike in one of my most favorite spots in the entire county. But finally we can now all enjoy the natural beauty of Annadel. The trails offers diverse terrain including the famed San Rosa oak trees, majestic redwoods and plenty of spring time wild flowers. The walks here are usually fairly well trafficked but you can find some solitude in the higher peaks. I would (if on foot) be very weary of the aggressive mountain bikers as often times they can come around at high speeds around blind curves. So be sure to keep an eye out as I have been witness to some pretty ugly injuries by both hikers and bikers.

Although this park is not dog friendly (which is probably the only downfall I could come up with about this beautiful place), I still have to give it 5 stars without a doubt. I've hiked here many times and today I decided to do a sunrise hike. I don't know many other places that open before sunrise so that's another nice thing about Annadel. There were an abundance of wildlife frolicking around and all you could really hear were the chirping of the birds and the trees blowing in the wind. The views were breathtaking the entire time. There are also so many different trails to explore, so it makes it a great place to visit over and over again. A lot of people like to run and bike the trail as well. My friend and I ended our hike with a picnic breakfast with a wonderful view all around us. I highly recommend checking out Annadel no matter what your hiking, biking, or running experience is. You won't regret it!

Annadel was hit hard during the 2017 fires but it's been open now for a while with all trails ready for action. I love that the park connects to easy access trails at Howarth Park which is so accessible to all levels of activity. Annadel packs a bit more punch as you climb up to Lake Ilsanjo or the marsh. It's so beautiful on all the trails. My favorite loop is Canyon around the lake and down Spring Creek but don't let that suggestion limit you - I love how many trails are connected on each side of the park. If you want to really mix it up you could park a car at each side and hike through the park from one side through to the other. Something like parking at Warren Richardson trail and climbing up over and around Ilsanjo and down canyon, rough go, or Spring creek. So many options!! It's especially lovely now with the lush grassy banks, babbling creeks with small waterfalls, beautiful green mossy trees oaks, and full Ilsanjo lake to be enjoyed! Get out there and enjoy it.

I have hiked this state park many times, offering tons of trails to explore all with beautiful views. Fulfilled with hikers, mountain bikers, runners this park is a fit for all, unfortunately no dogs allowed, but free parking. On my last hike me and my friend enjoyed hiking in the evening to enjoy the sunset it was a magnificent view. You will have to make sure to check out this state park when visiting sonoma county or if your a local.

Beautiful chunk of Sonoma County! Established in 1971, this area has an interesting history. It was originally inhabited by Wappo and Pomo people until the Spaniards showed up in 18th century. Then in 19th century it was purchased by William Hood, an Scottish immigrant. The ownership changed hands a few times after that. Then fast forward to a few decades ago and enter philanthropists Henry Trione and Joe Long who put up $5 million dollars to save the site as a park. The park is now about 5100 acres of beautiful land for all to enjoy. You'll see hikers, bikers and runners taking advantage of the nicely maintained trails. If it is your first time there, you may want to start with a trail that gets you to and around Lake Ilsanjo. It is beautiful there.

Well Santa Rosa is about food, beer and wine. It's also about trails, trails and trails. Annadel State Park is stellar for hiking, mountain biking, some road biking and selective dog walking on Channel Drive only. Santa Rosa area has been hit with a major rainstorm. Many lowland vineyards are underwater we noted driving south on the #101 Redwood highway from Oregon. But the Annadel trails are cut well, hard packed and drain well. Lots of beautiful oak's covered in moss and manzanita--awesome forest canopy to ride or hike under--I'm mountain biking on a fat tire with plus wide tires made for a little slip and slide in the mud in some places on the trail. The forest smells so fresh after all the rain! People are canoeing--really--in some of the meadows cuz there is so much water. Still the trails are sweet! There are lots of stream crossings and rock hoppings--a whole lot a fun. Got mud on me all over but I felt like a kid again slipin and slidin around the mountain. A blast! I highly recommend hitting this grand state park which is about 5 miles from Santa Rosa. Been here 3 times. It's definitely 5 stars ***** for Mother Nature!

Get a FREE park to hike at Annadel SP on Green Friday, 11/25/16 the day after Thanskgiving. Think this is my 2nd time at the park, first time was back in 2007! Lucky my friend Dave was able to drive so I didn't have to. It's 1.5hrs in the morning when we left SLZ at 8:30am, we got to the park by 10am. First stop was the Visitor Center got some information and used the indoor bathrooms - flushed toilets, single bathrooms 1 men/1 women. We parked at Horse Trailer Parking at the end of the road Channel Drive. There are 3 pit toilets there, 1 one locked. This park is overrunned by mtn bikers - be careful. No dogs allowed. We did these trails, think we did about 8-9 miles total: Channel Trail Live Oak Trail Rough Go Trail Orchard Trail Cobblestone Trail Loop Trail Lake Trail to see Lake Ilsanjo - it's just ok, not that impressive. Warren Richardson Trail Steve's S Trail Highlights: We saw 4 deer, a burned area, rock wall, some views. We might go back since we didn't go on all the trails. Parking as of 11/25/16 is $7; for seniors 62+ it's $6.

Love hiking here! Very beautiful and a variety of hiking/walking trails as well as picnic sites!

The only reason this isn't a five star review is because they do not allow dogs. The paths seem endless, which so many choices that can make the hikes more or less difficult depending on what you're looking for. They all loop back and intertwine with each other so you always end up where you want to go and easily find your way back to the car in the end. I've been hiking these trails since I was little and I will continue to hike them until I can't hike anymore. So beautiful with so much to offer.

Dinging this park one star because it is not dog friendly. This is a state park and dogs are generally not allowed on state trails. Other than that, this is a mountain bikers paradise with lots of wonderful trails to cruise down. There are trails that are mild to moderate in addition to steep trails. These trails are horse friendly as well. But horse rider beware, the bicyclists can whip by you on the trail scaring your horse. There are multiple entrances into the park and so much of the park to explore. Today we hiked to a lake up there. Which was rather full from all of the rain we've had.

Every time I hike at Annadel I am amazed at the beauty and sheer volume and length of all trails inside this park. It's such a big park! I'm pretty sure you could run 20 miles without every re-tracing your steps! I've not even come close to hiking all the trails here. The trails at Annadel range from dry, dusty, and rocky, to green and forested. I especially love the rough rockiness of all trails. There's nothing more fun than running down a steep and technical path.

Have always lived in close proximity to Annadel! Hiking and walk Trails; lakes, fishing, canoeing, snack bar, lots of happy shiny people walking THIER dogs.

This beautiful park is located in Santa Rosa and as a first timer, I was so happy to have selected this place to take a hike. It takes a bit of time to get into the actual park because there are several spots where you can start your hike, depending on your mode of transportation i.e. Foot, bicycle or even horse! But after you decide which trail you want to do you're in for quite the adventure! My boyfriend and I chose the lake trail and it was stunning! Although the lake wasn't much, we enjoyed the easy 5mile hike where we saw turkeys and lots of deer! Of course there is other wild life and lots of stuff to see, it's not over crowded with people either! Well we did manage to take a Friday hike so perhaps that's why there was minimal people. I highly suggest this park to anyone who is in the Santa Rose area that was to just get away for a moment.

Caution: This review is written by a gal who is NOT what you would call physically fit. All you professional mountain bikers and whatnot can disregard this one :P Came here at the suggestion of my fairly athletic boyfriend who wanted to go hiking on our Wine Country vacation. We chose a 4-mile path for a roughly 2 hour hike. I wish they would label the trails on difficulty.. Don't get me wrong, this might have been the easiest one anyway, but it was TOUGH on a non-hiker like me. Lots of uphill huffing and puffing and major soreness the next day. Good luck to my fellow big girls if you choose to make the trek ;) That said...... This park is BEAUTIFUL. The scenery is amazing, there's a ton of wildlife, and the other people on the trails are super friendly. We had a group of 4 deer run across the trail right in front of us, a hawk landed about 30 feet from me and took off again, and another hiker stopped to tell us about when he saw a mountain lion in one of the big fields. Great place for anyone who's into this stuff!

I only spent a short time here and went on one trail, but had a super serene hike on a Saturday afternoon. I chose to come here over Muir Woods for a number of reasons: I've been to Muir Woods a few times before and it can be a madhouse on the weekends. First thing to know about Annadel: it is THE spot that locals go to for mountain biking. On any given trail, you'll probably encounter a handful of mountain bikers and...watch out! They'll zip by you and you better get out of the way! Those looking for redwoods may be disappointed, while you may run across some sequoias, they are not the dominant tree and there are far and few in between (none that I came across that are huge). The park is also huge and there are many neighborhoods you can park in for free and then joining a trail, rather than going through the main entrance and paying the parking fee. Just look on a map. Great place for photography, to go for a walk or to mountain bike. Highly recommended!

So fortunate to have this park in our neighborhood, It is a magnificent Jewel as parks go . You can spend all day hiking

Disclaimer: Healthy man who exercises/runs 3-4 times a week. We were around the Napa Valley area for the weekend and did 3 hikes. This is probably our least favorite one but still has its charm. Signs: Signs for the trails are pretty clear except you need to know which direction you are going. Elevation: It's very moderate. A bit steeper in the beginning but most of the trails are pretty flat. Trails: Some part of trails are not shaded. So wear your sunblock. There's not much going on along the trails. However, there's a lake towards the end. It was nice and relaxing. We also saw a few deer and a white crane. The trails are also very bumpy and uneven. I would say the only people who enjoy that much of vibration both in and out of the bedrooms are the mountain bikers we saw. Difficulty: I would say average. We did about 6.5miles round-trip in about 2hr15min. Average pace was about 20min/mile and elevation was 941ft

My favorite downhill trail so far is North Burma, but Cobblestone is growing on me. There are so many challenging trails in Annadel! I plan on riding all of them. I came across four groups of turkeys and a few deer last MTB ride. Gotta love the deep forrest and terrain. Annadel is therapy for the soul.

My parents house is right behind Annadel. Our backyard has a gate that puts us right onto Ridge Trail. Needless to say, I'm in Annadel all the time. I absolutely love it. It's great for Mountain Biking and hiking. If you're not an experienced Mt. biker annadel has some rough trails. My favorite time to be in Annadel is Spring and Fall. In the summer it gets pretty dusty out there and there is no shortage of snakes on a hot day. If you've never been it is worth a try. Ridge trail is awesome for mountain biking as well as Lawndale and Schultz.

Great spot for a short hike. There were longer hikes/walks available but we were happy with what we did in 2 hours. Lorne, the docent at the Visitors Center, was very helpful, and happily told us some fun historical local trivia. Because of the recent weather, he, along with a ranger we passed, expressed their concern about my footwear. I assured them all that I had different shoes for hiking. Ready for our hike, we waited at the outside tap to refill our water bottles. We waited five minutes for some woman to finish washing rocks (WTF?) before giving up and filling our bottles closer to the trail. The trails were great, the view was amazing, and we saw a jackrabbit! Totally super cute, romantic, and just really really great.

This is one of the unlucky state park that is in danger of budget cut closure. It is highly popular among equestrians and mountain bikers but hikers could enjoys an exclusive hiking-only path featuring a forest full of douglas fir and rolling grassland with various wild flowers. I did the Richardson trail to Steve's "S" Trail loop. The hike was rated moderate. Elevation change was gradual throughout. Not the most challenging hike but should give you a good workout. Love the scenic meadow view. I really hope we could keep this park open.

This is a beautiful place for hiking in Sonoma County. The trails are soft dirt and well maintained. There are all different types of trees up here. It feels like every bend you enter a new unique ecosystem. One minute you are in a dense forested area with trees so thick the light barely filters through, and the next you are standing in the middle of a meadow. As beautiful as it is, it is quite hilly so hiking up here is definitely good exercise. There are a number of parking areas in order to access the trails. Some are free while others have a small fee. There aren't any restrooms or water fountains in most parts of the park, so come prepared. This is definitely more nature-heavy than nearby Spring Lake. Much more peaceful and quiet up here. Just watch out for the occasional mountain biker whizzing by.

5000 acres of oaks, redwood, creeks, lakes, marshes, rocks and spectacular views. Awesome trail network for hiking, mountain biking, and horses. It's adjacent to Spring Lake and Howarth Park if you have dogs or little kids in your company.

Great for a stroll. A bike ride. Or a hike.

Great park. You would never think that it's as large as it is. Lots of fun trails, easy or hard. Also I always feel like I'm the only one here because it's so large you don't always run into people. I'm not too stoked on the 'no dogs' in state parks business, but I bring him anyways...haven't been caught yet. Just make sure you clean up their poop, and check for ticks when you get home...oh and if you see other people on the trail make sure you put them on their leash, sometimes the joggers get a little butt hurt and will give you shit. I usually just say sorry and keep walking. ;)

I love Annadel State Park. The path can be walked, biked, ran, skated, jogged, skipped, you name it. Everyone is very aware of their surroundings and keep a watchful eye out for everyone else which makes the activities so much more fun! The trees are gorgeous and have a lot of character, keeping the landscape bountiful and lush during summer/spring months. Make sure to bring a jacket since it can get a bit chilly in the mornings and evenings. Other than that, just bring a set of lungs and get some fresh air!

Camping, hiking, mountain biking, picnicking among wildflowers, fishing, Annadel offers a wide range of stuff to do here. This place has gone up in popularity in the last couple years so I recommend you come early to avoid the frustrations of finding a parking spot. They have several different trails that lead to the top of the mountain and personally I think they are all about the same level of difficulty. This hike is easier than it looks. It only has a few really steep parts to it, but most of the time it is pretty chill. There are a decent amount of signs on the hikes to let you know how much longer until your destination. I would say that this hike is a beginner/intermediate level hike.

THE BEST around for Mountain Biking. I have been riding all over California and surrounding states and Annadel is top notch as fair as trails, maintenance, etc. And the the singletrack.... AMAZING !!! To us mountain bikers, this place is a Mecca. Desiree N. the NO DOG policy is because their is a huge population of trail users that ride horses. And.... Dogs and horses don't really mix. Dogs bark + Horses running = Disaster !!! Not too hard to figure out. You have to yield to horses, because they are huge animals. And all of the equestrians I have encountered are very nice people. Also, I would like to add that they recently did some trail work on the Richardson Trail, some mounds that look like ski jumps... VERY FUN, but watch out for peeps and horses. Have FUN !!!

My backyard. Literally. I live adjacent to the park. Green forest, lots of hills to climb, trails to bike & hike, you'll spot deer, turkeys, chipmunks, skunk, etc... You can even trailer in your horse for a bucolic ride. $7 admission fee is the best money you've ever spent.

Taking off 1 star because this place is not dog friendly. Besides that, I have been here a few times & it's a great place to go enjoy a nice hike in nature! I went with my boyfriend a couple days ago, and it was very busy on a Sunday. We weren't sure where to go at a couple forks on the trail, but everyone we spoke to or asked a question to were so overly nice and in a great mood. Very clean trails, and once you get to the top (lake Ilsanjo) it is so worth it!

Such a BEAUTIFUL place to go hiking. Like everyone said, it is very packed with bikers, but there are also trails for just hiking. The hike-only paths are REAL hikes, not just paved paths like other parks. You truly walk into the woods, roots are staircases, trees fallen over in the paths. We saw wild turkey, bunnies, lizards, and several deer. A short drive from downtown Santa Rosa, totally worth it. One of my favorite places I've ever hiked.

Great park. Visiting from out of town but i had lived in the area 15 years ago. There are many ways to enter either from main park entrance to surrounding neighborhoods. While i was here i hiked up to the lake, saw waterfalls, a family of dear and a wild turkey. I also got in some geocaching as well. My only complaint was that some of the trails were not marked.

Great place to hike and enjoy the gorgeous scenery that Santa Rosa has to offer! My boyfriend and I recently discovered the amazing, scenic views of these trails and found that this is a great place to work out for anyone, at any age. I love the contrasts between the shady woods and open meadows that you hike through and definitely will be back to explore more!

Annadel is heaven. Nothing is more wonderful than just spending all day exploring their endless trails and getting lost in the forest. Endless lakes, ponds, vantage points, meadows, little wonders, etc. to stumble upon and keep you interested and inspired to keep exploring. A plethora of beauty all conveniently located so close to Sonoma county residents (fortunately under 5 mins from my home). Turn off your tv, get your ass off your couch and go for a hike in Annadel and you'll come back home a much happier, relaxed person ;)

Went hiking here with a friend. Secluded, well shaded, great views. Tons of trails to choose from. The hikes can be tough; you'll want to be very careful not to twist your ankles from all the rocks and uneven surfaces. Your shoes and pants will also get quite dusty from the hike so be prepared.

Such an amazing park with a great view. Good to take dogs on a walk, go on a scenic hike, or have a picnic with the family. Do pack lots of water because it's a lot of walking.

AMAZING!! Love Annadel been biking here for over 10 years and continue to find new trails!

A great place to ride trails of all levels. I recommend riding the fire access roads if you have kids. My boy got tossed around on Burma, but we survived.

Incredible diversity in this park. I come up for a yearly camping trip/mountain bike ride with friends. We get the group campsite which offers seclusion away from the other campers. The mountain biking takes you through technical, easy, fast flowing and all challenging and fun. The fauna is totally different from open rolling oaks, to chaparral, to pine forests. Highly recommend this park for camping, hiking and mtn. biking.

Great park not so crowded, plenty of greens to see perfect for job with dogs and kids

I love living in Sonoma County because you never have to go far to find beautiful scenery and great hiking trails. Annadel is amazing, and if you want a nice hike then check this place out.

I visited this park for the first time this weekend for some trail running with my husband and it was awesome. We were the first car parked in the lot ($6 fee @ Channel Dr. Entrance) although noticed quite a few cars parked outside the gates. We noticed the sign about the park closing soon and were saddened by it! We had a wonderful 11 mile trail run and really enjoyed every mile. When we got back to our car there were a total of 6 cars parked in the official lot. Upon leaving I counted 50 (FIFTY!) cars parked along the road where there is no fee collected. No wonder this park won't be staying open- people are too CHEAP! It's a shame because I hope to get back here and run more trails! (Remember State Parks have an annual parking pass priced from $90-$125- I'll be buying mine this week. SUPPORT THE PARK SYSTEM!)

Nice park with various trails! Recommended for nice stroll- moderate level difficulty.