It is the third-largest county in Oklahoma by area. The terrain of McCurtain county varies from the foothills of the Ouachita Mountains in the northern part of the county to the rich Red River bottoms of the southern part. Sections of the Mountain Fork and Little River drainages lie in McCurtain county. Glover River originates in McCurtain County and flows to its confluence with Little River southeast of Wright City. Broken Bow Lake was created in 1968 by damming the Mountain Fork River. Mountain Fork river is one of the two year round trout fisheries in the state. The lowest point in the state of Oklahoma is located on the Little River in McCurtain County, where it flows out of Oklahoma and into Arkansas.