21-31 West 73rd Street, 1925. Image above shows the south side of the Park Royal building from West 73rd Street. The Park Royal is a 15-story red brick prewar apartment building designed by architect George F. Pelham. Built around the time of the Dakota, which is just a block south on 72nd Street, the Park Royal was of the first “apartment hotels” constructed to appeal to the wealthy, to attract people out of their downtown townhouses and to the Upper West Side. Leases in the Park Royal included full-time staff, and individual units were sprawling. To preserve the view of Central Park, developers originally purchased a row of brownstones on either side of the building to prevent construction. In 1985, the building underwent conversion into a Cooperative.