Explore the World's Oldest Subway Tunnel
Even though New York has more exciting neighborhoods than just about anywhere else in the world, it can still be frustratingly difficult to find anywhere undiscovered, because everything is so overly-documented.
So here's one walking tour activity you won't find in your Lonely Planet book: climb down a manhole underneath Brooklyn's busy Atlantic Avenue and inside the world's oldest subway tunnel.
The Atlantic Avenue tunnel is a half-mile road that was built back in 1844, and then just completely forgotten about for decades until it was rediscovered in 1980. Today, Bob Diamond, who found the lost tunnel, takes groups down on expeditions. If you're already grossed out, we can say that at least from the photos, it looks a lot cleaner than any subway tunnel we've ever seen.
Tours take place once a month; the next one is Sunday, February 22. Bring a flashlight!
Photo: [Brooklyn Rail]