1. The original winding house stood here, foundations still visible. Original wooden headgear was replaced in 1921 by existing steel joist headgear.
The pit head is a stone and brick construction with steel joist superstructure. The tram circuit is conti
GGAT.

2. Big Pit was operated in connection with Blaenavon Ironworks Company, then by the National Coal Board from 1947 to 1980. Underground workings date from the early C19 but the shaft on this site was sunk c1860, then deepened in 1880. The headframe was built in 1921, replacing a wooden head frame, and was altered in 1952 by the NCB's 'Blaenavon Gang' when the new winder was built. The shaft continued in use to 1973 for winding coal and to 1976 as a means of access for the miners.

Steel headframe of lattice girder construction with a pair of circular sheaves. The pithead and tram circuit are stone and brick. The tram circuit is continuous with the pit head and consists of a loop of corrugated iron and brick sheds. On the N (downhill) side the pit head has a rubble stone plinth. Above this is brickwork incorporating 3 square-headed windows. The brickwork continues into the tram circuit, although here the elevation is mainly of corrugated iron. On the S side the pit head is mainly brick with with corrugated iron roof.

R Hayman, Hayman & Horton, 30/12/2002