Each year, over 10,000 cultural events take place in the city, including ten international theatre, music, and art festivals. The Ljubljana Festival is one of the two oldest festivals in former Yugoslavia (the Dubrovnik Summer Festival was established in 1950, and the Ljubljana Festival one in 1953). Guests have included Dubravka Tomšič, Marjana Lipovšek, Tomaž Pandur, Katia Ricciarelli, Grace Bumbry, Yehudi Menuhin, Mstislav Rostropovich, José Carreras, Slid Hampton, Zubin Mehta, Vadim Repin, Valerij Gergijev, Sir Andrew Davis, Danjulo Išizaka, Midori, Jurij Bašmet, Ennio Morricone, and Manhattan Transfer. Orchestras have included the New York Philharmonic, Israel Philharmonic, Royal Philharmonic Orchestra, Orchestras of the Bolshoi Theatre from Moscow, La Scala from Milan, and Mariinsky Theatre from Saint Petersburg. In recent years there have been 80 kinds of events and some 80,000 visitors from Slovenia and abroad. Other cultural venues include Križanke, Cankar Hall and the Exhibition and Convention Centre. During Book Week, starting each year on World Book Day, events and book sales take place at Congress Square. A flea market is held every Sunday in the old city. On the evening of International Workers' Day, a celebration with a bonfire takes place on Rožnik Hill.