NYC Guide: A hidden playground in Manhattan

I've lived in New York City for ten years, and I've had a baby for more than a year, but the other day I stumbled upon an amazing hidden playground that I had NO IDEA existed.
When you walk into Battery Park City, you see rows of tall apartment buildings. But if you walk behind the building 22 River Terrace, there's a cluster of big trees. They don't look like much, but if you head into them...
...you'll reach a clearing with a sandbox, splashy fountains, and giant slide! It feels like you're in the middle of a forest, and the 14-foot-tall slide feels surprisingly steep. Alex challenged me to slide down while holding my arms up (as if it were a roller coaster) and it was totally exhilarating. (I'd actually love to go back with grown-up friends sometime:) Toby adores it, too, of course, and I'd highly recommend Teardrop Park as a lovely little secret garden.

P.S. 19 best NYC playgrounds.
P.P.S. Coming up tomorrow: Where to eat and sleep in NYC... xoxo

(Photos by Smith & Ratliff)