• Children's Museum needs a timed ticket, a separate 90-minute slot best booked online; it is meant for kids 4 and up, and strollers stay in the cloakroom
• Weekend crowds around noon, when the building fills and entry pauses for 30 to 45 minutes, so come at opening or on a weekday
• One ticket covers both buildings, linked by an underground passage, except the Children's Museum

The Historical Building at the top of Wenceslas Square holds the natural history halls: a fin whale skeleton, life-size models of prehistoric animals, fluorescent minerals and meteorites, and the domed Pantheon.

An underground passage leads to the New Building and its hands-on Children's Museum, where kids explore nature and invention through interactive exhibits and games. Older kids can add the 20th-century history galleries.