Beyond the answers - interesting background to this quiz

The detective who outlived her creator

Agatha Christie introduced Hercule Poirot in her first published novel, The Mysterious Affair at Styles, in 1920. Over more than five decades he appeared in dozens of novels and short stories, making him one of the few fictional detectives to be killed off by his author and then brought back by popular demand. Christie eventually grew tired of her creation, yet readers never did - Poirot remains one of the most adapted characters in crime fiction.

A basin below sea level

Death Valley sits in the Mojave Desert, largely in eastern California near the Nevada border. Its lowest point, Badwater Basin, lies roughly 86 metres below sea level, making it the lowest land elevation in North America. The valley is also famously hot: it holds the record for the highest air temperature ever reliably measured on Earth, 56.7 degrees Celsius, recorded at Furnace Creek in 1913.

The crust is mostly oxygen - sort of

Oxygen is the most abundant element in the Earth's crust by mass, but almost none of it floats around as a gas. It is locked into minerals and rocks, chiefly in compounds such as silicon dioxide. Silicon comes second, which is why the two elements together make up the bulk of the ground beneath our feet.

Souvlakia and the island table

Souvlakia - small pieces of meat grilled on skewers - is one of the most recognisable dishes of Cyprus, where it is often served with pita, salad and lemon. Cypriot cooking blends Greek and Middle Eastern influences, shaped by the island's position in the eastern Mediterranean and its long history of trade and settlement. Similar skewered meats appear across the region under names like shish kebab and souvlaki.

An island with a long memory

Sardinia belongs to Italy, but it has a cultural identity distinct from the mainland. It is the second-largest island in the Mediterranean, and its interior preserves traditions, dialects and archaeological sites that long predate Roman rule. The island's isolation has helped keep its language and customs alive in a way that few other European regions can match.