Loudon
- Earl of Loudoun
- Governor General Loudon (ship)
- L'Oudon
- London (disambiguation)
- Loudon (CDP), New Hampshire
- Loudon (name)
- Loudon Classic
- Loudon County, Tennessee
- Loudon Park Cemetery
- Loudon Park National Cemetery
- Loudon Township, Carroll County, Ohio
- Loudon Township, Fayette County, Illinois
- Loudon Township, Seneca County, Ohio
- Loudon's Highlanders
- Loudon, New Hampshire
- Loudon, Tennessee
- Loudoun
- Loudoun County, Virginia
- Loudun
- New Hampshire Motor Speedway
- Otis, Massachusetts
