The maps maps produced by Ordnance Survey Ireland are called the Discovery Series. Discoverer Sheet No. 12 covers Strabane and includes Castlederg, Sion Mills and Newtownstewart.

The maps maps produced by Ordnance Survey Ireland are called the Discovery Series. Discoverer Sheet No. 12 covers Strabane and includes Castlederg, Sion Mills and Newtownstewart.