Budapest is the capital and the largest city of Hungary, and one of the largest cities in the European Union. Budapest has about 1.75 million inhabitants on an area of 525 square kilometers. Cited as one of the most beautiful cities in Europe, Budapest's extensive World Heritage Site includes the banks of the Danube, the Buda Castle Quarter, Andrássy Avenue, Heroes' Square and the Millennium Underground Railway, the second-oldest metro line in the world. It has around 80 geothermal springs, the world's largest thermal water cave system, second largest synagogue, and third largest Parliament building. The city attracts about 4.5 million tourists a year, and it is also ranked as "the world's second best city" by Condé Nast Traveler, and "Europe's 7th most idyllic place to live" by Forbes. The city may be known for its thermal baths but there are also plenty of other attractions such as the vast Buda Castle, the majestic Chain Bridge and the romantic Fisherman's Bastion. Budapest is a city of thermal baths, cafés, striking turn-of-the-century architecture, trendy ruin pubs and most of all, a city of the Danube. Straddling the wide river, which separates hilly Buda from level Pest, the Hungarian capital offers one of the most striking metropolitan panoramas in Europe. Budapest is a city of music, from the classics of Bartók and Kodály to the contemporary fusion of folk, klezmer, jazz, and Gypsy sounds. Long hidden behind the Iron Curtain, Budapest is rightfully regaining its reputation as one of the most vibrant capitals of central Europe.