Page "Strabane" Paragraph 16

The partition of Ireland in 1922 turned the boundary with County Donegal into an international frontier.

This changed trade patterns to the railways ' detriment and placed border posts on the Joint Committee's FV and S & L lines and on the GNR line to Derry.

Stops for customs inspections greatly delayed trains and disrupted timekeeping.

Over the next few years customs agreements between the two states enabled GNR trains between Strabane and Derry to pass through the Free State without inspection unless they were scheduled to serve local stations on the west bank of the Foyle, and for goods on all railways to be carried between different parts of the Free State to pass through Northern Ireland under customs bond.