The town sits at the bottom of a valley, all roads leading to the town follow hills, in particular the old Knock road (known as the Knock hill) and Courthouse road. Although low lying the town does not experience flooding. There is no major river through the town.
Claremorris is the fastest growing town in County Mayo. There was a 31% increase in the town's population between 2006 and 2011 and a 23% increase between 2002 and 2006.