Colorado - Criteria: C (architecture/engineering)
| Union Station |
| Union Warehouse |
| United Church of Christ of Highlandlake |
| United States Air Force Academy, Cadet Area |
| Upper Brush Creek School |
| US Bureau of Reclamation Project Office Building |
| U.S. Customhouse |
| US National Bank |
| U.S. Post Office |
| U.S. Post Office and Federal Building |
| US Post Office and Federal Building-Canon City Main |
| US Post Office and Federal Building-Delta Main |
| US Post Office and Federal Building-Monte Vista Main |
| US Post Office and Federal Courthouse-Colorado Springs Main |
| US Post Office-Boulder Main |
| US Post Office, Federal Building, and Federal Courthouse-Sterling Main |
| US Post Office-Florence Main |
| US Post Office-Fort Morgan Main |
| US Post Office-Lamar Main |
| US Post Office-Manitou Springs Main |
| US Post Office-Montrose Main |
| US Post Office-Rifle Main |
| US Post Office-Trinidad Main |
| Vail Hotel |
| Vaille, Agnes, Shelter |
| Valley View School |
| Van Briggle Pottery Company |
| Victor Downtown Historic District |
| Victor Hotel |
| Von Trotha-Firestien Farm at Bracewell |
| Waite, Davis, House |
| Walker Ranch Historic District |
| Wall Street Assay Office |
| Walter, Martin, House |
| Walters, Manuella C., Duplex |
| Ward Congregational Church |
| Warshauer Mansion |
| Washington Park |
| Wasson-McKay Place |
| Waycott, Ernest, House |
| Webber, Henry, House-Pioneer Park |
| Webster Building |
| Weckbaugh House |
| Weiser, Martha, House |
| Weld County Courthouse |
| Westcliffe Jail |
| Westcliff School |
| Westminster University |
| West Plum Bush Creek Bridge |
| West Side Court Building |
| Wetmore Post Office |
| Wheeler Bank |
| Wheeler Bridge |
| Wheeler Opera House |
| Wheeler-Stallard House |
| White School |
| Wild Basin House |
| Wild Basin Ranger Station and House |
| Wildhack's Grocery Store-Post Office |
| Wiley Rock Schoolhouse |
| Willow Park Patrol Cabin |
| Willow Park Stable |
| Wilson, Blanche A., House |
| Wilson, S.A., Elementary School |
| Windsor Town Hall |
| Wolfe, John, House |
| Woodbury, Joseph A., House |
| Wood-Morris-Bonfils House |
| Woodward-Baird House |
| Wrightsman House |
| Young Women's Christian Association |
| Yucca House National Monument |
| Y.W.C.A. |
| Zall House |
| Zang, Adolph J., House |
| Zang, Adolph, Mansion |
| Zion's German Lutheran Church |
| Zion, Walter and Anna, Homestead |
Data from United States Park Service and Wikidata
