Colorado - Significance region: Local
| Boulder Creek Bridge |
| Boulder Crescent Place Historic District |
| Boulder Valley Grange No. 131 |
| Bouton, Jay H., House |
| Bouvier-Lothrop House |
| Bowen Mansion |
| Bowles-Cooley House |
| Bowles House |
| Bowman, William Norman, House-Yamecila |
| Bradford House II |
| Bradford, Robert Boyles, Property |
| Brannan Sand and Gravel Pit #8-Lake Sangraco Boathouse Complex |
| Briarhurst |
| Bridge No. 10/Adelaide Bridge |
| Bridge over Arkansas River |
| Bridge over Burro Canon |
| Bridge over Fountain Creek |
| Brighton High School |
| Brinker Collegiate Institute |
| Bromley Farm-Koizuma Hishinuma Farm |
| Brook Forest Inn |
| Bross Hotel |
| Brown, David W., House |
| Brown, J. S., Mercantile Building |
| Brown, Molly, House |
| Brown's Canyon Bridge |
| Brueger Brothers Building and Annex |
| Brush, Jared L., Barn |
| Bryan Hose House |
| Bryant-Webster Elementary School |
| Buchan Cabin |
| Buckeye School |
| Buckley Ranch |
| Buena Vista Ranger Station |
| Building at 1389 Stuart Street |
| Building at 1390 Stuart Street |
| Building at 1435 Stuart Street |
| Building at 1444 Stuart Street |
| Building at 1471 Stuart Street |
| Bunce School |
| Burgess House |
| Burlington Gymnasium |
| Burlington Hotel |
| Burlington State Armory |
| Burro Mine Complex |
| Butters, Alfred, House |
| Byers Peak Ranch |
| Calamity Camp |
| Callahan, Matthew, Log Cabin |
| Callahan, T. M., House |
| Calvary Episcopal Church |
| Campbell, Richard Crawford, House |
| Canon City Downtown Historic District |
| Canon City Municipal Building |
| Canyon (Canon) Creek School, District No. 32 |
| Capilla de San Isidro |
| Capitol City Charcoal Kilns |
| Capitol Life Insurance Building |
| Cardiff Coke Ovens |
| Cardinal Mill |
| Carlile, James N., House |
| Carnegie Library |
| Carnegie Library |
| Carnegie Public Library |
| Carnegie Public Library |
| Carnero Creek Pictographs |
| Carrot Men Pictograph Site |
| Carter-Rice Building |
| Cascade Boy Scout Camp |
| Cascade Cottages |
| Castle Rock Depot |
| Castle Rock Elementary School |
| Cayton Guard Station |
| CB&Q Denver Shops Powerhouse |
| Central City Opera House |
| Central High School |
| Central Junior High School-Keating Junior High School |
| Central Platoon School |
| Central Presbyterian Church |
| Central School Auditorium and Gymnasium |
| Chadbourn Spanish Gospel Mission |
| Chaffee County Courthouse and Jail Buildings |
| Chaffee County Poor Farm |
| Chama Sociedad Proteccion Mutua de Trabajadores Unidos (SPMDTU) Lodge Hall |
| Chamber of Commerce Building |
| Chamber of Commerce Building |
| Chambers Ranch |
| Chappell, Delos Allen, House |
| Chateau, The |
| Chautauqua Auditorium |
| Cheesman Park Duplex |
| Cherokee Ranch |
| Cherry Creek Bridge |
| Chew, Rial, Ranch Complex |
| Cheyenne County Courthouse |
| Christ Episcopal Church |
| Christian Science Society Building |
| Christ Methodist Episcopal Church |
| Churches Ranch |
| Church of St. Philip-in-the-Field and Bear Canon Cemetery |
Data from United States Park Service and Wikidata
