On January 16, 1900, Theophilus Van Kannel received U.S. Patent No. 641,563 on the revolving door.

Actually there had been revolving doors before, including those shown in Van Kannel’s earlier U.S. Patent Nos. 387,571, 588,620, and 588,888, but his improvement was to allow the door to be collapsed “when direct ingress or egress is desired.”  For his work Van Kannel was inducted into the National Inventors Hall of Fame in 2007.