- Ireland1
- Isle Royale, Lake Superior, Keweenaw County, Michigan, United States1
- Isère, Rhône-Alpes, France1
- Italy1
- Jackson County, Georgia, United States1
- Jackson, Hinds County, Mississippi, United States1
- Jackson, Madison County, Tennessee, United States1
- Jacksonville, Duval County, Florida, United States1
- James River, Virginia, United States1
- Jeffrey, Boone County, West Virginia, United States1
- Jihocesky, Bohemia, Czech Republic1
- Johns Island, Charleston County, South Carolina, United States1
- Jonesville, Union County, South Carolina, United States1
- Joplin, Jasper County, Missouri, United States1
- Juan de la Chico Mine, Guanajuato, Mexico1
- Jumilla, Murcia, Spain1
- Kansas City, Jackson County, Missouri, United States1
- Kaskaskia River, Illinois, United States1
- Kelleys Island, Erie County, Ohio, United States1
- Kentucky River, Frankfort,Kentucky, United States1