Unexpected Discovery During First Tour Of Abandoned Subway Tunnel

BOSTON (CBS) - It's a rare opportunity to visit a unique, and usually unseen, part of Boston history, underground. A hundred lucky people got a chance Monday to go into an abandoned subway tunnel under Government Center. But while they were there, a new discovery. It's not just a tunnel.

The abandoned tunnel was built in 1898, just a year after Boston's first in the nation subway started running. The trains that used this tunnel ran from Scollay Sq., which is now Government Center, to the Adams Sq. station, which has been demolished. The tunnel closed in the early 1960's in order to build Boston City Hall. So City Hall Plaza is on top of it. "It was active for about 65 years before it was decommissioned," says Joe Bagley, Boston's City Archaeologist.

This is the first time the public has gotten to see this piece of Boston history. The first 100 people who signed up, got the tour from Bagley. "Everything on the walls, floors and ceiling is original. The arches on the roof are original. The little niches built into the wall, which would have protected the staff from oncoming trains, that is original," he says.

And just Monday, a new discovery, a white line on the floor. The visitors scuffed up the dirt to reveal it. It's the line you're supposed to stand behind when a train approaches. That means this was not just a tunnel, but a part of a station, the old Scollay Sq. station.

"It adds another layer to the story of what this space really is," says Bagley. "There's something so innately interesting about such a large, abandoned space in the heart of downtown Boston. It's just one of those places that very, very few people have had the opportunity to go down to."

Thousands of people applied for Monday's tours. With that kind of response the city is thinking about ways that more people can actually get that glimpse of history.