The 1837's first edition of the Ordnance Survey's 6-inch maps is now available.
It shows Sligo in the boundaries before the Local Government reform of 1898, i.e. before the DEDs east of Ballina (Ardnaree North, Ardnaree South Rural, and Ardnaree South Urban) were transferred from Sligo to Mayo.
Sligo County Library
Upper Right hand corner : -
"LOCAL MAPS COLLECTION"
ROSSESPOINT UPPER 1837