They were competing to connect the coal and raw material supplies of South Wales with the industrialised Midlands and Northwest; and secondly to transport passengers to and from London to the port of Liverpool.

Jointly constructed from 1902 to an enlarged standard LNWR design of 1876, the three storey structure is built of two storeys of red brick and cement, with a third floor mainly of wooden weather board pin-panel containing the glass windows, all topped by a Welsh slate pitched roof.

[2] The main operational floor houses a 180 lever interlocked frame, divided into two sections: Abbey Foregate to Sutton Bridge; Shrewsbury station to Crewe Junction.

[3][2] The signal box is a grade II listed building and underwent extensive heritage renovation in 2020-21, carried out by Network Rail.

Within 1 mile (1.6 km) of the junction, there are another three interlocked mechanical signal boxes: A further three boxes that had formed part of the local system: Network Rail currently believes that to simplify this system to allow it to be remotely controlled through colour-light signals would not be economical.