Colorado - Criteria: C (architecture/engineering)
| Neusteter Building |
| Newberry House |
| New Brick-The Brick Saloon |
| Newman Block |
| New Terrace |
| Nichols House |
| Nordlund House |
| Norlin Quadrangle Historic District |
| Norman Apartments |
| North Inlet Trail |
| North La Junta School |
| North Rim Road, Black Canyon of the Gunnison National Park |
| North Seventh Street Historic Residential District |
| North St. Vrain Creek Bridge |
| North Weber Street-Wahsatch Avenue Historic Residential District |
| Notch Mountain Shelter |
| Nunns, John Herbert, House |
| Ochsner Hospital |
| Ogden Theatre |
| Ohio-Colorado Smelting and Refining Company Smokestack |
| Old Colorado City Historic Commercial District |
| Old Livery Stable |
| Oltjenbruns Farm |
| Opera House Block/Central Block Building |
| Oriental Theater |
| Orman-Adams House |
| Osgood Castle |
| Osgood Gamekeeper's Lodge |
| Osgood-Kuhnhausen House |
| Ouray City Hall and Walsh Library |
| Ouray Historic District |
| Our Lady of Mount Carmel Church |
| Overland Cotton Mill |
| Owen Estate |
| Oxford Hotel |
| Pacific Express Stable |
| Palace Hotel |
| Palmer Hall |
| Palmer, Judge Peter L. House |
| Paonia First Christian Church |
| Paramount Theater |
| Parish, Harvey J., House |
| Park County Courthouse and Jail |
| Park Hill |
| Park Theatre |
| Parry, William D., House |
| Pauline Chapel |
| Pearce-McAllister Cottage |
| Peck House |
| Pedro-Botz House |
| Peoples Presbyterian Church |
| Peterson House |
| Peters Paper Company Warehouse |
| Petrelli-DelPizzo House |
| Phillips County Courthouse |
| Phillips, Harry and Lilly, House |
| Pierce-Haley House |
| Pike's Peak Grange No. 163 |
| Pine Hall |
| Pioneer Cabin |
| Pioneer Sod House |
| Pipe Line School |
| Pitkin County Courthouse |
| Plaza de San Luis de la Culebra |
| Pleasant Valley School |
| Pleasant Valley School |
| Plum Bush Creek Bridge |
| Plummer School |
| Poncha Springs Schoolhouse |
| Ponderosa Lodge |
| Powell and Blair Stone Ranch |
| Prowers Bridge |
| Prowers County Building |
| Pryor, Frank, House |
| Public Service Building |
| Pueblo City Park Zoo |
| Pueblo County Courthouse |
| Pueblo Federal Building |
| Pueblo Mountain Park |
| Pyramid Guard Station |
| Quaintance Block |
| Queen of Heaven Orphanage Summer Camp |
| Rainbow Arch Bridge |
| Rankin Presbyterian Church |
| Ray Apartments Buildings |
| Raymond, Wilbur S., House |
| Red Cliff Bridge |
| Red Rocks Park District |
| Redstone Coke Oven Historic District |
| Redstone Historic District |
| Redstone Inn |
| Reimer-Smith Oil Station |
| Rhoades House |
| Rialto Theater |
| Rice, Ida M., House |
| Rice, Ward, House |
| Richards Mansion |
| Richthofen Castle |
| Richthofen Place Parkway |
| Rico City Hall |
Data from United States Park Service and Wikidata
