Towns
| State | City/Town | Town Title |
|---|---|---|
| Colorado | Hygiene | Hygiene, CO |
| Colorado | Idaho Springs | Idaho Springs, CO |
| Colorado | Idalia | Idalia, CO |
| Colorado | Idledale | Idledale, CO |
| Colorado | Ignacio | Ignacio, CO |
| Colorado | Iliff | Iliff, CO |
| Colorado | Indian Hills | Indian Hills, CO |
| Colorado | Jamestown | Jamestown, CO |
| Colorado | Jaroso | Jaroso, CO |
| Colorado | Jefferson | Jefferson, CO |
| Colorado | Jessica | Jessica, CO |
| Colorado | Joes | Joes, CO |
| Colorado | Johnstown | Johnstown, CO |
| Colorado | Julesburg | Julesburg, CO |
| Colorado | Karval | Karval, CO |
| Colorado | Keenesburg | Keenesburg, CO |
| Colorado | Kersey | Kersey, CO |
| Colorado | Kim | Kim, CO |
| Colorado | Kiowa | Kiowa, CO |
| Colorado | Kirk | Kirk, CO |
| Colorado | Kit Carson | Kit Carson, CO |
| Colorado | Kittredge | Kittredge, CO |
| Colorado | Kobe | Kobe, CO |
| Colorado | Kremmling | Kremmling, CO |
| Colorado | La Jara | La Jara, CO |