The County of Paintearth No. 18 is a municipal district in east central Alberta, Canada. Located in Census Division No. 7, its municipal office is located southeast of the Town of Castor near the intersection of Highway 12 and Highway 36.

Castor is a town in Alberta, Canada. It is located at the intersection of Highway 12 and Highway 861, approximately 143 km (89 mi) east of the City of Red Deer. It has an elevation 816 m (2,677 ft).