The Warsaw Marathon is an annual marathon event which takes place on the streets of Warsaw, Poland. It is the oldest annual marathon in Poland, held since 1979. The marathon is organized by the non-governmental organization Fundacja Maraton Warszawski. The race usually takes place on the last Sunday of September.

Warsaw, officially the Capital City of Warsaw, is the capital and largest city of Poland. The metropolis stands on the River Vistula in east-central Poland. Its population is officially estimated at 1.86 million residents within a greater metropolitan area of 3.27 million residents, which makes Warsaw the 7th most-populous city in the European Union. The city area measures 517 km2 (200 sq mi) and comprises 18 districts, while the metropolitan area covers 6,100 km2 (2,355 sq mi). Warsaw is an alpha global city, a major cultural, political and economic hub, and the country's seat of government. It is also capital of the Masovian Voivodeship.