A linear complex of manganese mining features, extending at least 3km from north to south, associated with the Egryn and Haffotty mines (Nprn33973, 401809) and centred at SH61902037 and SH61701818 respectively. Manganese extraction in this area began between 1835 and 1840, with a main period of extraction from 1886. Some parts reopened in 1917.

Source: Crew & Musson 1996 'Snowdonia from the Air', 53.

J.Wiles, RCAHMW, 5 November 2004.