This junction, also known as Foulshiels Junction, was immediately south of the level crossing by the former Foulshiels station. There was a long passing loop on the main route running south from the junction, accommodated by the line here having been prepared for two tracks, and a short passing loop on the branch line.
The junction was formed in 1869 when the Addiewell Branch (North British Railway) (a goods and minerals line) was opened from the 1850 Longridge to Bathgate (Edinburgh and Glasgow Railway).
Around 1894 the loop was altered, extended at the north end through the former Foulshiels station, and the signal box replaced. Headshunts were provided at either end of the loop, the loop and headshunts on what would have been the westbound line had the line been built as double.
The signal box survived until 1963 when the Addiewell branch closed. The railway closed here altogether in 1966.