Jim B.
Yelp
First: A little data - a web search tells me that this estimated 220 acres was once home to an exhibition grounds.
On the south end (actually in Planterwald below Bulgarische Strasse) is an abandoned amusement park - the kind of place that industrial decay photographers love. There is an island in the Spree that has concerts when the weather is good and in the southwest is a rather large and lovely lake.
At the NE corner, right near the Sbahn stop (how many parks have their own Sbahn stop?) is a debarkation point for cruises on the Spree and various food establishments.
Also on the south is The Archenhold Observatory, where Einstein gave his first lecture on relativity and where you can take the kids for an astronomy lesson. I have not yet been inside, next time for sure.
So - how do I say 'not much here' without sounding snarky?
220 acres is a huge space - and in that huge space are precious few useful things like, oh, park benches, trash cans and pavilions. I'm certain that the size and waterfront location is the draw here, but I'm the kind of guy who likes to sit and observe whats happening, and its hard to do if there is nowhere TO sit.
Plus, running through the middle of the place is a racetrack of a road called Pushkin Allee. Really? Bisect a giant park with what is really a highway? Yeah, um, bad design work there. The slice between that slab of asphalt and the river is a pretty nice place overall - mostly because of the river view. OK. Totally due to the river view.
OK: Now the centerpiece of the western section is a gigantic Soviet era monument to the 7000 (5000? conflicting details in what I read) Red Army soldiers who died taking Berlin. Its an interesting piece of work, part propaganda and part memorial. I'm a huge fan of the excesses of Social Realism, and this one is actually restrained compared to many of that era. Perhaps as it serves as grave marker for so many fighting men.
BUT: be warned, there are only two entrances, and the gate on the south was locked up tight when I got there. And its a damed long trudge through the mud to get to the other end. I lost 20 minutes of light because of that. Idiots. Plan to go to the North end, there are two ceremonial arch entries facing east and west near that end.
The giant socialist statue features a sword wielding soldier standing on the crushed remains of a swastika, holding a child. Not subtle at all, but effective for sure. Inside is a mosaic that you can only see a small part of that is quite beautiful and symbolic. Its the least over the top part of this space, and the one thing you simply cannot really see all of. Pity.
EDIT TO ADD: I later found out that many Berliners call this guy "The Tomb of the Unknown Rapist". The Soviet army was not kind to the population of Berlin when they took it down.