The first student union in America was Houston Hall, at the University of Pennsylvania, which opened January 2, 1896 and remains in operation to this day. The first Ohio Union at Ohio State University was Enarson Hall. The building opened in 1911 and was the first student union to be built at a state university and the fourth of its kind in the United States. Oklahoma State University's student union opened in 1950. Subsequent additions, and renovations in 2010, have made the building one of the largest student activity centers in the world at .