Thornton Marshalling Yard, Hump Box

Thornton Marshalling Yard extended for 1.5 mi, with six reception sidings and 35 sorting sidings. Independent up and down avoiding lines sandwiched the yard, with the passenger lines set to the south of the yard. It had a single hump at the west end, so traffic was sorted towards the easterly direction over a central hump which had two lines, each having of these lines had a retarder. The practice of sorting both up and down traffic in one location avoids the need to have two towers and two sets of staff sorting the traffic. Thornton was the first yard in Britain built with a set of secondary retarders to help slow the speed of the wagons descending off the hump. The hump had been built to…