Marsh Pit Colliery is depicted on 1881 Ordnance Survey mapping, and was disused by 1899. The site is immediately north-west of a reservoir (depicted as marsh on historic Ordnance Survey mapping), and is now part of business park. The marsh Pit Colliery site is some 800m north-north-east of Pit Mawr (Great Pit) Colliery (NPRN 301194).

N Vousden, RCAHMW, 22 May 2013