Photos of the abandoned subway tunnel beneath City Hall

City archaeologist Joseph Bagley ducked as he passed through a door in an abandoned subway tunnel under City Hall Plaza on Monday.
City archaeologist Joseph Bagley ducked as he passed through a door in an abandoned subway tunnel under City Hall Plaza on Monday.
Jessica Rinaldi/Globe Staff

A photographer knelt in an abandoned subway tunnel under City Hall Plaza.
A photographer knelt in an abandoned subway tunnel under City Hall Plaza.
Jessica Rinaldi/Globe Staff

The view inside an abandoned subway tunnel.
The view inside an abandoned subway tunnel.
Jessica Rinaldi/Globe Staff

A municipal officer shined his light inside an abandoned subway tunnel.
A municipal officer shined his light inside an abandoned subway tunnel.
Jessica Rinaldi/Globe Staff

The view of an abandoned subway tunnel under City Hall Plaza.
The view of an abandoned subway tunnel under City Hall Plaza.
Jessica Rinaldi/Globe Staff

Municipal officer Marc Voltus shined his flashlight inside an abandoned subway tunnel.
Municipal officer Marc Voltus shined his flashlight inside an abandoned subway tunnel.
Jessica Rinaldi/Globe Staff

Tracks inside an abandoned subway tunnel.
Tracks inside an abandoned subway tunnel.
Jessica Rinaldi/Globe Staff

Members of the media checked out an abandoned subway tunnel.
Members of the media checked out an abandoned subway tunnel.
Jessica Rinaldi/Globe Staff

A door rested underneath a staircase in an abandoned subway tunnel.
A door rested underneath a staircase in an abandoned subway tunnel.
Jessica Rinaldi/Globe Staff

Adams Square Station, looking southerly, circa 1898.
Adams Square Station, looking southerly, circa 1898.
City of Boston Archives/Flickr