It's beautiful, has a nice walkway, and a pretty lake with swan boats that you can take out for half an hour or more. In the morning- save for exercise enthusiasts- the place is virtually empty, so it's a great place to unwind with a book and coffee in hand, go for a jog, or morning stroll. Saturday mornings it is also usually quite quiet, with the occasional Vietnamese-style photo shoot. The park tends to get quite upbeat at night, with food, kites, music, people out roller skating, playing badminton, kids in electric cars, etc, etc. There is a small carnival section near the boat rental that has some rides for kids. The park has a few gazebos to sit under to beat the heat, as well as grass that can be played on! There are also some neat paths, bridges, and small hills. We love to bring our football / frisbee here, as there are a lot of different spaces to run around - it is much bigger than most parks in Hanoi.