Salzburg is the fourth-largest city in Austria and the capital of the federal state of Salzburg. Salzburg's "Old Town" (Altstadt) with its world famous baroque architecture is one of the best-preserved city centres north of the Alps, and was listed as a UNESCO World Heritage Site in 1997. The city is noted for its Alpine setting. Salzburg was the birthplace of 18th-century composer Wolfgang Amadeus Mozart.