Trains and FlixBus are cheap; book PKP Intercity early

PKP Intercity trains between Warsaw, Kraków, Gdańsk, and Wrocław are comfortable and inexpensive when bought a few weeks out; Pendolino express fares rise close to the date. FlixBus and Polish bus lines cover the gaps for less. In cities, single tram and bus tickets are sold at machines on board and at stops and must be validated. Warsaw's and Kraków's museums have a free day each week; the Warsaw Uprising Museum's is Monday, the Rising's details change.