Gniezno Cathedral

The Royal Gniezno Cathedral is a Brick Gothic cathedral located in the historic city of Gniezno that served as the coronation place for several Polish monarchs and as the seat of Polish church officials continuously for nearly 1000 years. Throughout its long and tragic history, the building stayed mostly intact, making it one of the oldest and most precious sacral monuments in Poland.The cathedral is known for its twelfth-century, two-winged bronze doors decorated with scenes of martyrdom of St. Adalbert of Prague and a silver relic coffin of that saint. The coffin was made by Peter von der Rennen of pure silver in 1662 after the previous one, established in 1623 by King Sigismund III Vasa himself, was robbed by the Swedes in 1655, during the Swedish invasion.The temple is one of Poland's national Historical Monuments, as designated on September 16, 1994, and tracked by the National Heritage Board of Poland.

Source: Wikipedia