- Kameiros (ancient city), Rhodes3
- Katimin (historic village), Klamath River, Siskiyou County1
- Kepel, Klamath River, Humboldt County1
- Klamath Lake, Klamath County, Central Oregon1
- Klamath River, Humboldt County, California3
- Klamath River, Siskiyou County, California1
- Klazomenai (ancient city), Ionia2