Hong Kong Science Museum

The Hong Kong Science Museum is the best all-round answer to a wet day in the city: cheap, fully indoor and packed with things to press, pull and pedal. It opened in 1991 in Tsim Sha Tsui East, and its permanent galleries now hold more than 500 interactive exhibits across 6,500 square metres. This is a museum for doing, not reading. The centrepiece is the Energy Machine, a 22-metre, twin-tower kinetic sculpture that climbs through four storeys of the building. A stream of balls rolls along roller-coaster tracks across the two towers to show how energy changes from one form to another. It is billed as the biggest machine of its kind in the world, and it is worth timing your visit to catch a full run. Also on show is Betsy, the DC-3 that was Cathay Pacific's first airliner. Around them, themed halls cover light and sound, mechanics, the patterns of mathematics, and magnetism and electricity. The Biodiversity Gallery deals with plants and animals, and the Environmental Conservation Gallery takes on climate and sustainability. Younger children have their own Children's Gallery, which works as a gentle first taste of science. Special exhibitions change through the year and have covered polar research, climate change, dinosaurs, robotics and science fiction. Standard tickets are HK$20. Full-time students get in free, and the permanent exhibition is free for everyone on Wednesdays, which makes a Wednesday downpour the cheapest possible day to come. The box office closes an hour before the museum, so arrive with time to spare. Tickets can be bought up to a week ahead through URBTIX, which saves time at the counter on a busy wet weekend. The Museum of History next door is an easy add-on if the rain keeps going.