the main line ran northwards, climbing and in a cutting and passing under a farm overbridge near londonderry farm, and then through a long bridge under the present-day a4175 (keynsham to willsbridge) road. continuing across the field, the londonderry branch ascends and joins the main line, which then runs to willsbridge, where there was a "wharf". the line crossed the turnpike road (the present-day a431) on the level immediately to the west of the road junction, entering a cutting and then a tunnel long; this area is now occupied by a water company. on the north side of the tunnel, the line ran in a deep rock ccutting, now accessible as "the dramway", a local walking route, and the line curved round the western shoulder of the hillside to a point known as tramway junction, where the california colliery branch trailed in.