If you intend to visit several museums during your stay, consider purchasing a Prague Card (www.praguecard.com), which offers free or discounted entry to around 50 sights. Included are Prague Castle, the Old Town Hall, the National Gallery museums, the Jewish Museum, the Petřín Lookout Tower and Vyšehrad.
Prague Card passholders are entitled to free public transportation on metros, trams and buses, including the Airport Express transfer bus from the airport to the main train station.
The pass is available for two to four days, starting at around 1450/1075Kč per adult/child for two days.
Cards can be purchased at Prague City Tourism offices, public transport information centres as well as select hotels and travel agencies around town. They can also be purchased online through the card website.