Mankin Barn

By Luke Anderson

August 13, 2015

The Mankin Barn is located on the former Keeline/4J Ranch outside Gillette, Wyoming. The barn was built for the Keeline brothers in 1908, and has served as a horse barn ever since. The Keeline brothers were reportedly some of the first people to bring cattle ranching in the Wyoming Territory north of the Platte River when they first arrived in 1877. Their strong influence in the ranching and herding industry resulted in a town near Lusk, Wyoming to be named after them.

The Mankin Barn lies just outside of Gillette, WyomingThe Mankin Barn lies just outside of Gillette, Wyomin

The barn itself is significant as well. At 9,600 square feet and standing nearly 40 feet high, the Mankin Barn is purportedly the largest intact historic horse barn in the United States. It can house 40 Percheron workhorses and the loft can support 150 tons of hay. The barn also once served as a community center, hosting basketball games and dances. The barn features two stories, massive sliding doors on the east and west ends, and a distinctive “4J” brand in bright red on the front. It sits on a stacked stone foundation that has been reinforced in areas with concrete at a later date.

This building is not on the National Register for Historic Places, but the building is both historically and architecturally significant. The Keeline brothers who had the barn built were important contributors to the early development of ranching culture in Wyoming, important enough to have a town named for them. The building is one of the largest historic horse barns in America and remarkably still serves the same purpose as it did when it was built in 1908. The building is representative of longevity, resilience, and community.


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This project was funded in part by a Historic Architecture Assistance Fund grant, and completed by CTA Architects and Engineers. The program is offered by the Alliance for Historic Wyoming in partnership with Wyoming Main Street and the Wyoming State Historic Preservation Office, and is made possible by a grant from the Wyoming Cultural Trust Fund