If you're planning to visit a number of museums in a short time, it's worth buying the Carte Musées et Monuments (1-day ?12.20, 3-day ?24.39, 5-day ?36.59), available from the tourist office, métro stations, museums, and the Eurostar terminal at London Waterloo. Valid for seventy museums and monuments in and around Paris, the pass allows you to bypass ticket queues (though it doesn't provide entry to special exhibitions and you will still need to queue up for security checks). Reduced admission is often available for those over 60 and under 18, for which you'll need your passport as proof of age, and for students under 26, for which you'll need an ISIC (International Student Identity Card). Many museums and monuments are free for children under twelve, and nearly always for kids under four. Under-26s can also get a free Youth Card, Carte Jeune , available in France from youth travel agencies like USIT and from main tourist offices (?18.29, valid one year), which entitles you to reductions throughout Europe. Some museums have free or half-price admission on Sunday; many are closed on Monday and Tuesday.