Third Lanark Athletic Club was a Scottish football club based in Glasgow. Founded in 1872 as an offshoot of the 3rd Lanarkshire Rifle Volunteers, the club was a founder member of the Scottish Football Association (SFA) in 1872 and the Scottish Football League (SFL) in 1890. Third Lanark played in the top division of the SFL for the majority of the club's existence, and won the league championship in 1903–04. The club also won the Scottish Cup twice, in 1889 and 1905. Third Lanark went out of business in 1967, as a result of mismanagement, six years after having finished in third place in the SFL. Third Lanark's former ground, Cathkin Park in Crosshill, is still partially standing and is used for minor league football.
In 1996, an amateur football club called Third Lanark was founded, with intentions of restoring the club's name to senior football, and returning to play regularly at Cathkin Park. In 2008 the club was reformed again and currently has an amateur team and four youth teams.