From 14 June 1943 a siding for the US Marines' camp at McKays Crossing with a crossing loop and tablet station was opened; near where the Wellington Tramway Museum is now located. With duplication of the track from Paekakariki to McKays Crossing and automatic signalling from Paekakariki to Paraparaumu, McKays Crossing was relay worked from the Paekakariki South signal box from December 1943. But on 25 March 1946 the catch points and two cross-overs of the siding were lifted, and McKays Crossing became the point where the double-track section north ended.