The places travellers dream about for years: world-famous sights worth planning a whole trip around. Each one links to what to know before you go - the best time of day and year, how long to allow, what to book ahead - and to its city guide.
1. Colosseum, Rome
The Colosseum in Rome is the largest standing amphitheatre in the world, a monumental gateway into the ambition of Imperial Rome.
Best time: Go early in the day, since queues for Rome's most popular attractions can exceed an hour and crowds only build as the morning goes on.
Colosseum: what to know before you go · Rome travel guide
2. Eiffel Tower, Paris
A wrought-iron lattice rising over Paris, best climbed with a plan and seen again after dark.
Best time: Go early: arrive at least 30 minutes before opening time, since the tower is one of Paris's choke points and waits of an hour or more are normal.
Eiffel Tower: what to know before you go · Paris travel guide
3. Statue of Liberty, New York City
A copper symbol of freedom in New York Harbor, rich in history and best seen up close.
Best time: Go early in the day, since this is one of the city's most popular landmarks and crowds and lines build quickly.
Statue of Liberty: what to know before you go · New York City travel guide
4. Tower Bridge, London
Walk 42 metres above the Thames inside a Victorian bascule bridge whose Gothic towers were built to match the Tower of London.
Best time: Go early in the day, since that generally beats the crowds at any popular landmark.
Tower Bridge: what to know before you go · London travel guide
5. Louvre Museum, Paris
A former royal palace on the Seine holding some of Western art's most famous works and eight departments spanning prehistory to today.
Best time: Arrive early in the morning, since popular locations draw long queues later in the day.
Louvre Museum: what to know before you go · Paris travel guide