Jay Cooke is noted for its Rustic Style historical structures. These structures were built by the Civilian Conservation Corps between 1933 and 1942. All the major landmarks in Jay Cooke are built with local basalt or gabbro stone and dark planks and logs. Most famous of all landmarks is the swinging bridge, which is one of only two suspension bridges in any Minnesota state park. The bridge was designed by Oscar Newstrom. It runs long, of which run over the river itself. It is supported by two large concrete pylons also faced with gabbro. The bank of the river near the River Inn is too steep to walk along, so anyone who wishes to hike the length of the river generally must cross this bridge.