YOUNG   TRAVELERS

What this section is for. Mexico City explained to children — and it is a city that rewards the attempt, because so much of its history is visible rather than abstract.

What children can actually see. A pyramid in the middle of the capital: the Templo Mayor, found in 1978 by electricity workers a few metres from the cathedral. A castle on a hill where an emperor lived, in the middle of a forest with a free zoo. Boats painted with flowers on canals that are the last piece of a lake the city was built on. Masked wrestlers at the Arena México. And a museum designed for children to touch everything.

The three facts that explain the city. It was an island, built on a lake, and the lake was drained — which is why the buildings lean. It was the capital of the Mexica, who founded it in 1325 after seeing an eagle on a cactus, the image on the Mexican flag. And it sits in a basin ringed by volcanoes, two of which can be seen on a clear morning.

Practical notes. Under-fives travel free on public transport. Most museums charge little or nothing for children and close on Mondays. At 2,240 metres, bring water, a cap and sunscreen.