Gardiner is a city in Kennebec County, Maine, United States. The population was 5,961 at the 2020 census. Popular with tourists, Gardiner is noted for its culture and old architecture. Gardiner is a nationally accredited Main Street America community. It is included in the Augusta, Maine micropolitan New England City and Town Area.

Kennebec County is a county located in the South-central portion of the U.S. state of Maine. At the 2020 census, the population was 123,642. Its county seat is Augusta, the state capital. The county was established on February 20, 1799, from portions of Cumberland and Lincoln Counties. The name Kennebec comes from the Eastern Abenaki /kínipekʷ/, meaning "large body of still water, large bay."