Beyond the answers - interesting background to this quiz

A river that crosses borders

The Congo is the deepest river in the world, with depths exceeding 220 metres in places, and the second longest in Africa after the Nile. Its vast basin drains parts of several countries, including the Democratic Republic of the Congo, the Republic of the Congo, the Central African Republic and Angola. The river has long served as a vital transport route through dense rainforest, where roads are scarce and boats often remain the most practical way to move people and goods.

Two capitals, one continent

Africa has 54 recognised sovereign states, and three of them are represented among the capitals in this quiz: Burundi, with its political capital Gitega, and Guinea, with its coastal capital Conakry. Gitega became Burundi's political capital in 2019, though Bujumbura, the former capital, remains the country's economic centre. Conakry, meanwhile, sits on a peninsula jutting into the Atlantic and is Guinea's largest city by a wide margin.

Roman numerals that still surround us

Roman numerals were not built for arithmetic the way our decimal system is; they grew out of tallying and recording, and the subtractive principle (placing a smaller numeral before a larger one, as in IV or IX) came later. DC equals 600, but the same letters appear on clock faces, film credits, monarchs' names and even the Super Bowl. Their persistence is partly aesthetic: they lend a sense of weight and tradition that plain digits rarely match.

The Olympics return to Britain

London hosted the 2012 Summer Olympics, making it the first city to stage the modern Games three times, after 1908 and 1948. The Games were held mainly in a newly built park in Stratford, east London, and the opening ceremony, directed by Danny Boyle, drew a global television audience in the hundreds of millions. The host nation finished third in the medal table, behind the United States and China.

A painting that was never meant to impress

Vincent van Gogh painted "The Starry Night" in 1889 while staying at the Saint-Paul-de-Mausole asylum near Saint-Rémy-de-Provence. The view is partly imagined: the village below the swirling sky is not one he could see from his window, but a composite drawn from memory and earlier sketches. Van Gogh considered the work a study rather than a finished masterpiece, yet it became one of the most recognised paintings in Western art.