Colorado - Significance region: Local
| Gray, Garret and Julia, Cottage |
| Greeley Downtown |
| Greeley High School |
| Greeley High School and Grade School |
| Greeley Junior High School |
| Greeley Masonic Temple |
| Greeley, Salt Lake and Pacific Railroad-Stout Branch |
| Greeley Tribune Building |
| Green Mountain Ranch |
| Greenwood Cemetery |
| Greenwood Lodge |
| Gregory, William J., House |
| Grimm, S. A., Block |
| Guerrieri-Decunto House |
| Guiraud-McDowell Ranch |
| Gully Homestead |
| Gunnison River Bridge I |
| Gunnison River Bridge II |
| Gwynne-Love House |
| Hagerman Mansion |
| Hahns Peak Schoolhouse |
| Hallett, Samuel I., House |
| Hamburger, George, Block |
| Hamill House |
| Hammar, Benjamin, House |
| Handy Chapel |
| Hanging Flume |
| Hanigan-Canino Terrace |
| Hargreaves Homestead Rural Historic District |
| Harmony Mill |
| Harms Farm |
| Harris Park School |
| Harris, W. C., House |
| Hart, Wilson A., House |
| Haskell House |
| Haxby House |
| Hayden Co-Operative Elevator Company |
| Hayden Depot |
| Hayden Ranch Headquarters |
| Hayden Rooming House |
| Hay's Ranch Bridge |
| Hazelhurst |
| Head Lettuce Day-Collegiate Peaks Stampede Rodeo Grounds |
| Heister House |
| Helene Apartment Building |
| Hendrie and Bolthoff Warehouse Building |
| Henkel-Duke Mercantile Company Warehouse |
| Henry Huff Cabin |
| Hewes-Kirkwood Inn |
| Highland Park Historic District |
| Highland School |
| Highlands Masonic Lodge |
| Hill Section, Golden Hill Cemetery |
| Hiwan Homestead |
| Hog Park Guard Station |
| Holden Mining and Smelting Co. |
| Holdsworth House-Aspenholme-Pines Lodge |
| Holland-Thompson Property |
| Hollemon-Smith Homestead and Ranch |
| Holly City Hall |
| Holly Gymnasium |
| Holly Santa Fe Depot |
| Holly SS Ranch Barn |
| Holmes, David Hull, House |
| Holy Cross Abbey |
| Holzwarth Historic District |
| Hope Lutheran Church |
| Hopkins Farm |
| Hose House No. 2 |
| Hotchkiss Hotel |
| Hotel Boulderado |
| Hotel de Paris |
| Hotel Holly-Haswell Hotel |
| Hotel Jerome |
| Hotel Meeker |
| Hotel St. Regis |
| House at 1750 Gilpin Street |
| Hoverhome and Hover Farmstead |
| Hover, W.A., and Company Building |
| Howard Store |
| Hudson, Sim, Motor Company |
| Huerfano Bridge |
| Huerfano County Courthouse and Jail |
| Huerfano County High School |
| Hugo Municipal Pool |
| Humboldt Street Historic District |
| Humphrey House |
| Hutchinson Ranch |
| Hyman-Brand Building |
| Hynes, Thomas, House |
| I and M Building |
| Iglesia de la Inmaculada Concepcion |
| Iglesia de San Francisco de Assisi |
| Iglesia de San Pedro y San Pablo |
| Iliff Hall |
| Indian Park School |
| IOOF Hall |
| Jackson, F.A., House |
| Jackson, George, House |
| Jacobs Building |
Data from United States Park Service and Wikidata
