See also: List of trading posts in Colorado and List of ghost towns in Colorado. This is a list of military and trading forts established in what is now the U.S. State of Colorado.
The initial forts, built in the first half of the 19th century, were early communities of commerce between Native Americans, trappers, and traders. William Butler, who wrote about the fur trade in Colorado, stated that there were 24 trading posts built in the pre-territorial area of what is now Colorado. The trading posts were of varying sizes. Gantt's Post had several small wooden buildings located along Fountain Creek. Near Pueblo, Fort Le Duc (Buzzard's Roost) was a small settlement. Bent's Old Fort was a large adobe stockade on the Arkansas River. Multiple trading posts were built along a 13-mile stretch of the South Platte River in the late 1830s: Fort Jackson, Fort Lupton, and Fort Vasquez. In the early 1840s, the fur trade collapsed and most of the trading posts were closed, although some served early communities of miners and farmers. Bent's Old Fort continued to operate as it was located on the Santa Fe Trail, serving people from the United States and the New Spain areas of what is now New Mexico.[1]
| style=text-align:left | Name | Other names | Location | Current county | Year founded | Year abandoned | Type | Status |
|---|---|---|---|---|---|---|---|---|
| Pike's Stockade | Sanford | Conejos | 1807 | 1807 | U.S. Army stockade | Reproduction[2] | ||
| Spanish Fort | Fort Sangre de Cristo | Sangre de Cristo Pass | Costilla | 1819 | 1821 | Spanish Army fort | ||
| Fort Talpa | Farisita | Huerfano | 1820s | Spanish post | [3] | |||
| Fort Uncompahgre | Fort Robidoux | Delta area | Delta | 1820s | 1844 | Trading post | Reconstruction | |
| Gantt's Picket Post | Fort Gantt | Las Animas | Bent | 1832 | 1834 | Trading post | No remains | |
| Fort Cass | Pueblo area | Pueblo | 1834 | 1835 | Trading post | No remains | ||
| Fort Convenience | Welby area | Adams | 1834 | 1835 | Trading post | No remains | ||
| Bent's Old Fort | Fort William | La Junta area | Otero | 1834 | 1849 | Trading post | National Historic Site and museum[4] | |
| Fort Le Duc | Fort Maurice, Buzzard's Roost, El Cuervo | Wetmore area | Custer | 1830s | 1854 | Trading post | No remains | |
| Fort Vasquez | Platteville | Weld | 1835 | 1842 | Trading post | Restored and museum | ||
| Fort Jackson | Ione area | Weld | 1837 | 1838 | Trading post | Foundation remains | ||
| Fort Lupton | Fort Lawrence | Fort Lupton | Weld | 1837 | 1844 | Trading post | Reconstructed | |
| Fort Saint Vrain | Fort George, Fort Lookout | Platteville | Weld | 1837 | 1855 | Trading post | Historical marker | |
| Fort Gerry | Kersey area | Weld | late 1830s | 1840s | Trading post | |||
| Milk Fort | Fort Leche, Pueblo de Leche, Fort El Puebla, Peebles Fort, Fort Independence | Las Animas | Otero | late 1830s | Trading post / settlement | No remains | ||
| Fort Davy Crockett | Fort Misery | Browns Park National Wildlife Refuge | Moffat | late 1830s | Trading post | |||
| Fraeb's Post | Fort Fraeb | Steamboat Springs area | Routt | 1840 | 1841 | Trading post | No remains | |
| El Pueblo | Fort Pueblo, Fort Nepesta, Fort Fisher, Fort Juana, Fort Spaulding, Robert Fisher's Fort | Pueblo | Pueblo | 1842 | 1854 | Trading Post | No remains[5] | |
| Fort Huerfano | Avondale | Pueblo | 1845 | Encampment | No remains[6] [7] [8] | |||
| Mormon Battalion and The Vanguard Company of 1847, Mormon Trail | Fort Independence | Pueblo | Pueblo | 1846 | 1847 | Mormon homes | No remains | |
| Fort Massachusetts | Fort Garland | Costilla | 1852 | 1858 | U.S. Army fort | Archaeological site | ||
| Bent's New Fort | See Fort Lyon 1 | Lamar area | Bent | 1853 | 1860 | Trading post | Foundation remains | |
| Fort Garland | Fort Garland | Costilla | 1858 | 1883 | U.S. Army fort | Reconstructed | ||
| Fort Namaqua | Modena's Crossing, Namaqua Station, Mariano's Crossing, Big Thompson, Miraville | Loveland | Larimer | 1858 or 1859 | 1868+ | Trading post | Historical marker at Namaqua Park[9] [10] | |
| Fort Mary B | Fort Independence, Fort Independent, Fort Breckenridge, Fort Meribeh | Breckenridge | Summit | 1859 | Stockade | No remains[11] | ||
| Fort Lyon 1 | Fort Fauntleroy, Fort Wise | Lamar area | Prowers | 1860 | 1867 | U.S. Army fort | Destroyed by fire[12] | |
| Fort Weld | Denver | Denver | 1861 | 1865 | U.S. Army post | Historical marker at 8th/Vallejo | ||
| Camp Collins / Fort Collins | Fort Collins | Larimer | 1862 | 1867 | U.S. Army camp / fort | No remains[13] | ||
| Francisco Fort | Fort Francisco | La Veta | Huerfano | 1862 | 1902 | Civilian fort | Refurbished, now a museum[14] | |
| Fort Morgan | Camp Tyler, Camp Wardwell | Fort Morgan | Morgan | 1864 | 1868 | U.S. Army post | Historical marker in city park | |
| Fort Wicked | Merino | Logan | 1864 | 1868 | House | Historical marker at US-6/CR-26 | ||
| Fort Sedgwick | Post at Julesburg, Camp Rankin, Fort Ranking | Sedgwick | Sedgwick | 1864 | 1871 | U.S. Army post | Historical marker | |
| Fort Reynolds | Avondale | Pueblo | 1867 | 1872 | U.S. Army post | Historical marker | ||
| Fort Lyon 2 | Las Animas | Bent | 1867 | 1897 | U.S. Army post | |||
| Fort Lewis 1 | Cantonment at Pagosa Springs | Pagosa Springs | Archuleta | 1878 | 1880 | U.S. Army post | Site is a city park | |
| Fort Flagler | Camp at Animas City | Durango | La Plata | 1879 | Temporary stockades | |||
| Fort Meeker | Cantonment on White River | Meeker | Rio Blanco | 1879 | 1883 | U.S. Army camp | Quarters refurbished, museum | |
| Fort Lewis 2 | Hesperus | La Plata | 1880 | 1891 | U.S. Army post | Converted to Indian boarding school | ||
| Fort Crawford | Cantonment at Uncompahgre | Montrose | Montrose | 1880 | 1891 | U.S. Army post | Historical marker | |
| Fort Narraguinnep | Dolores area | Montezuma | 1885 | Rancher's fort | U.S. Forest Service sign | |||
| Fort Logan | Fort Sheridan | southwest Denver | Denver and Arapahoe | 1887 | 1946 | U.S. Army post | One building is a museum |