Špilberk Castle has dominated the skyline of Brno for over seven hundred years. Today, it is a highly visited destination, but there have been times in the history of Brno when the fortress inspired fear, and represented oppression for the citizens of Brno. Over the course of the centuries, the importance of Špilberk and the part it has played have changed considerably. From a major royal castle and the seat of the Moravian margraves, it gradually turned into a huge baroque fortress, the heaviest prison in the Austro-Hungarian empire called the "dungeon of the nations“, and later a barracks. Today, Špilberk Castle houses its 40th year of the Brno City Museum, and is one of the most significant cultural centers in Brno. It was certified as a national heritage monument in 1962. In the summer season, the castle courtyards and other premises come alive with various cultural events including concerts, theater performances and historical shows, as well as sports competitions. Over 100,000 people visit the museum exhibitions annually.