There is a lot to do, there is a large pond to sit around and relax, watch the ducks which happen to be very large, if you're a kid you can get inside a floating gerbil ball and roll around on the water. You can also walk on the room of the stadium but it was too cold when we were there. And you can also go up the Olympic Tower.
Unfortunately, when we visited the visibility was minimal, but it still offered very nice views.
Hours - 9am - Midnight, 7 days a week, last elevator @ 11:30pm
Cost - 5.50 €