Loudon may refer to:
Places In the United States: Loudon, Massachusetts, formerly a constituent part of Otis, Massachusetts Loudon, New Hampshire Loudon (CDP), New Hampshire Loudon, Tennessee Loudon County, Tennessee Loudoun County, Virginia Loudon Township, Fayette County, Illinois Loudon Township, Carroll County, Ohio Loudon Township, Seneca County, Ohio
Other uses Loudon (name) The New Hampshire Motor Speedway, in Loudon, New Hampshire Loudon Classic, a motorcycle race held there Loudon's Highlanders, 18th century infantry regiment of the British Army Loudon Park Cemetery in Baltimore, Maryland Loudon Park National Cemetery in Baltimore, Maryland Governor General Loudon (ship), mail steamer, named after James Loudon, present at the Krakatoa eruption
See also Loudoun, an area in Scotland Earl of Loudoun John Claudius Loudon Scottish gardener, designer, author and planner L'Oudon, a commune in Calvados department, France Loudun, a commune in Vienne department, France London (disambiguation) Louden (disambiguation)