From Gloucester, the A48 runs through the villages of Minsterworth, Westbury-on-Severn, connects to a link road to Cinderford in the Forest of Dean then through Newnham, Blakeney and bypassing the town of Lydney (the bypass was built in the 1990s) on the west bank of the River Severn.
There were many branches to various collieries and a 'Mineral Loop' line was built to avoid reversal at Cinderford and the steep gradient from Speech House Road to Serridge Junction.