Boston & Lowell Railroad

Reporting mark: B&L
MBTA - Concord River Bridge (Middlesex County, Massachusetts)
Built 1832; extensively modified and encased in concrete 1908; timber trestle added 1931
Stone arch bridge over Concord River on MBTA Lowell Line
Open to traffic

MBTA - Mystic River Bridge (Middlesex County, Massachusetts)
Built 1835, extensively modified 1906
Closed-spandrel arch bridge over Mystic River on MBTA Lowell Line
Open to traffic