This weekend marked the seventh annual Open House New York celebration, which grants public access to many architecturally-significant and culturally interesting landmarks in the NYC area not otherwise open often (or ever, in some cases). The program this year featured loads of really exciting tours, many of which sold out in advance.

I opted to try and grab tickets for the Atlantic Avenue Tunnel tour, and to my good fortune, I was able to reserve two spots before it sold out. The tour takes you down below the street level into the world’s oldest subway tunnel, which was lost for decades until a man named Bob Diamond rediscovered its location in 1980. After excavating the tunnel and trying (without success) to petition the city government to put it to good re-use, Diamond founded an organization to lead tours, preserve its history, and promote the tunnel as a fascinating historical landmark in New York city history. Check out his organization’s website (and full history of the tunnel) here.

I can heartily recommend the tour, which they give monthly, and with plenty of excitement, I brought my tripod and a flashlight. Check out my Open House photos and captions below!

Two volunteers from the Open House New York staff and BHRA set up traffic barriers and remove the manhole in the intersection of Atlantic Avenue and Court Street in Brooklyn.

The tour guide led groups of us down into the tunnel via the manhole in the middle of the street. That felt pretty awesome, as the cars were zooming by. Strangely, you couldn't really hear much street noise at all.

After coming down through the manhole, we entered the antechamber. This is where Bob Diamond crawled through and made his discovery.

This shot is from near the end of the tunnel, not 200 yards from the Hudson River and New York Bay. There is a giant stone wall at the end of the tunnel, in which they believe that an old steam engine is buried. Let's hope that the city and powers that be grant them money to excavate and find out!!