Flags of Europe Quiz

The five Nordic crosses are the easiest group once you fix the colours: Denmark is red with a white cross, Sweden blue with yellow, Finland white with blue, Norway red with a blue cross outlined in white, Iceland blue with a red cross outlined in white. The cross is always shifted towards the hoist.

Horizontal tricolours are where the mistakes happen. Russia, Slovenia and Slovakia are all white–blue–red; only Russia is plain, while Slovenia and Slovakia add a coat of arms near the hoist. The Netherlands and Luxembourg are both red–white–blue, but Luxembourg's blue is a lighter sky shade and the flag is longer. Austria and Latvia are both red–white–red; Latvia's red is a deep maroon and its white band is thin. Hungary is red–white–green; Bulgaria is white–green–red.

Vertical tricolours have their own pairs: Italy (green–white–red) and Ireland (green–white–orange); Belgium is black–yellow–red vertically, Germany the same colours horizontally; Romania is blue–yellow–red, Andorra and Moldova the same but with arms. Then the singletons: Portugal's armillary sphere, Cyprus's copper-coloured island, Malta's George Cross, Albania's black double-headed eagle, Croatia's red-and-white chequerboard, and the square flags of Switzerland and Vatican City.