In 1906, an end-on junction was made at Cessnock station for a short branch to Aberdare Extended Colliery. In 1911, a branch line was constructed off the Aberdare Railway main line at Bellbird Junction (near Cessnock) to Bellbird Colliery by the Hetton Coal Co, which entered into an agreement with the East Greta Co for coal haulage. In 1916, this branch was extended to Pelton Colliery which was being developed by the Newcastle Wallsend Coal Co. In 1913, Caledonian Collieries constructed a branch line off the Aberdare railway main line to Aberdare South Colliery, and this was followed in 1914 by a separate branch to Aberdare Central Colliery.