Lailah J.
Yelp
This is a fantastic activity to do in the Hudson Valley, with gorgeous sweeping views of the river and the valley below. The walkway is the world's longest elevated pedestrian bridge, spanning 1.28 miles connecting Highland NY on the west side of the Hudson River to Poughkeepsie on the east side. At an average walking pace, it takes about 30-40 minutes to cross the entire bridge, but don't forget to account for the same distance walking back.
If you get tired midway or don't want to walk the WHOLE bridge, you can take a shortcut "cheat" by taking a glass elevator down/up by the Poughkeepsie waterfront, which by my estimation saves you 0.6 miles (if walking from Highland to Poughkeepsie), which is almost half the distance!
You could also do a longer 4.6-mile loop crossing back on the Mid-Hudson Bridge (Walkway Loop Trail).
In any event, I definitely recommend a stopover along the promenade of the Poughkeepsie waterfront and Upper Landing Park, where you can get a magnificent shot of the bridge and have a rest & snack.
Parent hack: If you have kids, there is a wonderful children's museum, the Mid-Hudson Discovery Museum (see my separate review for this), right on the waterfront. It's a great place to take a break and cool off while the kids have fun. This is where the elevator is so you can turn back at this point or continue along the bridge.
Bicycles are allowed but as the walkway is crowded with pedestrians, cyclists have to ride slowly. We debated whether to bring our bikes but in the end are glad we did the experience by foot.
There are volunteers along the length of the bridge to answer questions and tell you its history. The walkway used to be a rail bridge built in the 1880s and was converted to a pedestrian walkway that opened to the public in 2009.
The pavement gets HOT! and even in mid-80s degree weather the pavement can get up to 100 degrees and burn your pet's paws. We were there on the sizzling Memorial Day weekend and saw many people carrying their pets. Obviously there is no shade/covering on the bridge so plan accordingly and bring sunscreen, water, hat/cap, and maybe a parasol if needed.