Dimitrios Loundras was a Greek gymnast who competed at the 1896 Summer Olympics in Athens. He was the last surviving participant of these Games. Loundras competed in the team parallel bars event. Loundras was a member of the Ethnikos Gymnastikos Syllogos team that placed third of the three teams, winning a bronze medal. At 10 years and 218 days he remains the youngest medalist and competitor in Olympic history. This excludes the competitors of unknown ages who competed as coxswains in the 1900 Olympics. Loundras later became an officer in the Hellenic Navy, and reached the rank of Rear Admiral. In 1936 he served briefly as Prefect of Lesbos Prefecture.