Prague is the heart of the Czech Republic and is often considered one of the most beautiful cities in the world. With beautiful sights such as the Charles Bridge, Prague Castle and the Prague Astronomical Clock in the Old Town Square, the city is a popular tourist destination. A major attraction is Prague Castle, the largest continuous castle complex in the world and the most important symbol of the Czech Republic, a UNESCO World Heritage Site. The castle complex is a collection of palaces and religious buildings, including St Vitus' Cathedral, which houses the Czech crown jewels. The medieval astronomical clock in the Old Town is unique. Legend has it that the astronomical clock is the work of the master Hanuš, who went blind after completing his work and was unable to create another. There is also a large Jewish quarter with a town hall, 6 synagogues and the largest Jewish cemetery in Europe. Every house and street in Prague has a long history told through architecture and legends.