Bundesbad Alte Donau, Public swimming center in Donaustadt, Austria

Bundesbad Alte Donau is a public swimming facility on the Alte Donau in Vienna's 22nd district with large water areas and extensive green spaces. The site connects swimming zones through wooden jetties and pathways, offering different bathing areas for various visitors.

The facility was established in 1919 as a military swimming school and later transformed into a public recreation area after World War II. This shift reflects how postwar Vienna repurposed military spaces for civilian enjoyment.

The site opened on 20 June 1919 as a military swimming school, and only in the 1950s did civilians gain access. It is owned by the Republic of Austria and administered by the Burghauptmannschaft, the body that manages former imperial and federal buildings. Its listed-monument status covers the whole 61,000 m² grounds on the Arbeiterstrandbadstraße bank.

The bath lies on the centre-side bank of the Alte Donau at Arbeiterstrandbadstraße 93, near the Donaupark in Donaustadt. Of its roughly 61,000 m², about 17,500 m² is water and 43,500 m² land, so bathers and sunbathers use separate zones. It is a summer bath, run by the Burghauptmannschaft for the Republic of Austria.

The site was opened on 20 June 1919 as a military swimming school and only became accessible to the general public in the 1950s. It is owned by the Republic of Austria and administered by the Burghauptmannschaft, and its two gatehouses received a cantilevered roof during the 2011 renovation.