Montgomery County is located in the southeastern corner of the U.S. state of Arkansas. It is bordered by Yell, Logan, Scott, Polk, Jefferson and Bradley counties. The population was 11,281 at the 2010 Census. The county seat and largest city is Mount Ida. Montgomery County was formed in 1842 from parts of Clark and Hot Spring counties. It is home to Lake Ouachita State Park, which provides recreational opportunities including swimming, fishing boating and camping.