This was the junction between the Doura Branch of the Ardrossan and Johnstone Railway and the curve onto the Glasgow, Paisley, Kilmarnock and Ayr Railway.
Around 1900 a new curve was added from the junction to the Misk Colliery Branch, which entered the Ardeer Peninsula from the north. This allowed approach to that branch from the west (and supplimented a branch from Stobbs Junction to the east, allowing access from the east). This curve was to become particularly useful for serving the Ardeer explosives works during its expansion in the Great War - and survived the closure, in 1932, of the curve from Stobbs Junction.
The junction was just to the east of where the Lanarkshire and Ayrshire Railway passed underneath. The signal box was on the south side of the junction. This was a double track junction. To the west there was a loop, starting at the junction, on the westbound line which ran west to Dubbs Junction.
The Doura line closed around 1952, when the signal box closed. The Byrehill Junction to Dubbs Junction line is now single track and goods only.