Ostrow Tumski is an island between two branches of the river Warta in Poznan. Today it is one of the main attractions of the city.

The first settlement was built on the island in the 8th-9th centuries. And in the 10th century settlement on the island became one of the main political centers. Archaeological excavations conducted here in 1999, showed that the island was Ducal Palace in the place where now is the Church of the virgin Mary. It is assumed that the Palace chapel was owned by the wife of the Polish Prince Mieszko I. the adoption of the Polish ruler of Christianity on the island was built the first Cathedral, and the island became the property of the bishops. The population of the island at that period was about 200 people, the Cathedral was surrounded by a shaft height of about 10 meters, the total length of which was 2 km away.

After the invasion of Bratislava I, the island was recovered from their losses Duke Casimir I the Restorer, however, soon Poznan has lost its political importance. Special contribution to the development of the island made a Bishop Jan Lubanski, who in 1518 he founded the Academy, which remained higher educational institution to 1780. Also, during his reign on the island there were plumbing and paved streets. The Cathedral, which was rebuilt in Gothic style in the 14th and 15th centuries, was severely damaged in a fire in 1622, after which it was again rebuilt in the Baroque style. After Poznan was ceded to Prussia in 1793, the population of ostrów Tumski was 304 people. In 1800 the island was officially included in Poznan.

The island has suffered during the capture of the city by the red Army in 1945. Restoration work was carried out until the 1960s. Today Ostrow Tumski – the main tourist attraction of the city. Of special interest here are: the Cathedral, the Archbishop's Palace, the Church of the blessed virgin Mary from the 15th century, Academy Lubanski, where at the moment is the diocese Museum.