The south-facing junction from the Horwich Branch onto the main line at Blackrod was added in 1887, as part of the changes associated with the opening of the L&Y's new Locomotive Works at Horwich. Horwich Fork Junction was the last addition to the lines surrounding Blackrod and completed the triangle, allowing traffic to move between Horwich and Manchester without a reversal at Blackrod Junction.

Horwich Fork Junction signal box was a Railway Signal Company standard design fitted with 26 lever Railway Signal Company frame which initially only controlled the junction with the Horwich Fork line. In 1891 lever frame was extended to 28 levers to allow Red Moss Junction signal box which controlled the junction with the Hindley line to close, the Hindley line being extended a short distance and the junction being moved to Horwich Fork Junction signal box. The lever frame was further extended to 30 levers at some time, being numbered A-B, 1-28. The line from Loco Junction to Horwich Fork closed on 31 January 1967 and the Hilton House line to Dobbs Brow Junction closed on 09 September 1968, but the box seems did not close until 14th September 1969, leaving Blackrod Junction signal box controlling the line as far as Lostock.

Howrich Fork Junction SB, visible under Red Moss bridge, taken from a Horwich -Bolton service. The Hilton House branch to Hindley can be seen leaving the main line to the right of the main lines, just beyond the signal box. Photo : Alan Castle

Looking in the same direction, but taken from a position betwen Horwich Fork SB and the junction of the branch to Hilton House, this railmotor set is running from Bolton to Horwich (the loco is propelling). Photo: Peter Fitton

Looking back towards the station, this photograph was taken from the same position as the previous photo. Horwich Fork SB which controlled both Horwich Fork junction (just beyond the bridge) and the Hilton House branch to Hindley which was just a few yards in the other direction. The photo shows shows a Bolton to Horwich railmotor service, just months before the closure to passengers of the Horwich Branch.  Photo: Peter Fitton

Thanks to David Ingham for this article, and to Chris Littleworth for his excellent book  "Signal Boxes on Lancashire & Yorkshire Lines: North and West of Manchester", which provides the definitive reference source for signalling in the area.