Beyond the answers - interesting background to this quiz

A capital built on a drained lake

Mexico City sits in the Valley of Mexico, on the site of Tenochtitlan, the island capital of the Aztec Empire. When the Spanish arrived in the sixteenth century, they found a city surrounded by a shallow lake system, which they gradually drained to control flooding and expand the settlement. That engineering decision still shapes daily life: parts of the modern city are slowly sinking as the ground beneath them compacts.

The quietest hazard on Kilimanjaro

Mount Kilimanjaro is often described as a technically straightforward climb, which can make it sound easier than it is. Its real danger is altitude. The mountain rises to roughly 5,895 metres, and the rapid gain in elevation leaves many climbers struggling with acute mountain sickness. Fatalities are rare, but they are usually linked to altitude-related illness rather than falls or bad weather.

When the ears ring without a sound

Tinnitus is the perception of noise - often a ringing, buzzing or hissing - that has no external source. It is not a disease in itself but a symptom, commonly associated with hearing loss, loud noise exposure or ear injury. Because the sound is generated internally, it can be frustratingly hard to measure, and treatments tend to focus on managing the condition rather than silencing it.

Dickens and the Christmas book that stuck

Charles Dickens wrote A Christmas Carol in 1843, and it was published just before Christmas that year. The story of Ebenezer Scrooge and his overnight transformation helped revive and reshape Victorian ideas about Christmas generosity, and it has never been out of print since. Its ghosts have been reinterpreted on stage and screen countless times.

Monet and the art of the same view

Claude Monet, born in Paris in 1840, built much of his reputation on painting the same subjects again and again under different light and weather. His series of haystacks, Rouen Cathedral and water lilies were not repetitions but studies in how a single scene could change from hour to hour. That obsession with light helped define Impressionism, a movement named, initially mockingly, after one of his paintings.