The Portpatrick Railway had opened between Castle Douglas and Portpatrick in 1861–1862 and the Caledonian Railway worked that railway; it obtained running powers over the G&SWR between Dumfries and Castle Douglas, and at a stroke the Caledonian had penetrated deep into the south-west, and to the ferry service to the north of Ireland, territory that the G&SWR had assumed was its own.