Budapest service in and around Budapest, three lines of which are operated under the name HÉV. The river Danube flows through Budapest on its way from Germany to the Black Sea. The river is easily navigable and so Budapest historically has a major commercial port at Csepel District and at New Pest District also. The Pest side is also a famous port place with international shipping ports for cargo and for passenger ships. In the summer months, a scheduled hydrofoil service operates on the Danube connecting the city to Vienna. BKK (through the operator BKV) also provides public transport with boat
Budapest there are forty theatres, seven concert halls and an opera house. Outdoor festivals, concerts and lectures enrich the cultural offer of summer, which are often held in historical buildings. The largest theatre facilities are the Budapest Operetta and Musical Theatre, the József Attila Theatre, the Katona József Theatre, the Madách Theatre, the Hungarian State Opera House, the National Theatre, the Vigadó Concert Hall, Radnóti Miklós Theatre, the Comedy Theatre and the Palace of Arts, known as "MUPA". The Budapest Opera Ball is an annual Hungarian society event taking place in the building of the Budapest Opera ("Operaház") on the last