The daily Selkirk to West Springfield manifest is about to emerge from the east portal of the State Line Tunnel on CSXT's Berkshire Subdivision. This is the old Boston and Albany mainline, and this particular tunnel was bored in 1912. The adjacent bore dates from the line's construction in 1840 (as the world's first mountain railroad) but was abandoned in 1988 when Conrail single tracked part of the route.