Fans of the TV show "Life After People" would probably enjoy the Catskills. It seems you can't spit in these mountains without hitting an abandoned movie theatre, a decaying bungalow colony, a depopulated resort, or an entire zoo being swallowed up by the surrounding forest.
Thanks to Jeremiah of Common Sense in Ulster and Beyond for digging up this YouTube video (above), posted earlier this summer, of the abandoned Catskill Game Farm slowly being absorbed by the elements. The music's a little schmaltzy, but for those with fond memories of the Game Farm -- a group that probably includes most people who grew up in the Catskills and upper Hudson Valley -- the shots of weeds overtaking the animal pens and empty snack bars still cheerfully advertising fries and pizza will probably elicit a genuine pang.
Related: Here's a video of kids feeding baby pigs at the Catskill Game Farm in 2006, a few days before the 73-year-old park closed its doors and auctioned off all the animals. (It's inexplicably set to "Solitary Man" by Johnny Cash, which is maybe a little bit of overkill in the weepy-soundtrack department.) Its author has disabled embedding, so you'll have to click the link.