OKARMO Corner, Tripoint monument near Southwest City, Missouri, US

OKARMO Corner is a monument near Southwest City, Missouri, where the borders of Oklahoma, Arkansas, and Missouri meet. It consists of a concrete pedestal erected in 1915 by the Ozark Culture Club, topped by an older stone thought to date from the 1820s. Each side of the pedestal is engraved with a state name and its admission year: Missouri 1821, Arkansas 1836, and Oklahoma 1907. A fourth side bears the club's inscription.

The tripoint was first surveyed in the early 19th century after the Missouri Compromise of 1820 set Missouri's western boundary. The original stone marker, marked "Mis. 1821" and "Ark.", fell into disrepair and was rediscovered by a local farmer. In 1915 the Ozark Culture Club set it atop a concrete pedestal engraved with each state's admission year, and the Lions Club of Southwest City restored the monument in 1955.

The name OKARMO combines the initials of the three states: Oklahoma, Arkansas, and Missouri. Visitors can stand at one spot and experience being in three states simultaneously, creating a direct connection to how state boundaries shape the land.

The monument sits along Missouri Route 43, about one mile south of Southwest City, and is free to visit year-round. Visitors can park at paved road shoulders and should watch for traffic when crossing the road and exploring the area.

The top stone is inscribed "Mis. 1821" and "Ark.", abbreviations that identify it as a product of an early boundary survey rather than a modern replacement. It sits above a concrete pedestal whose fourth face credits the Ozark Culture Club, the group that installed it in 1915.