Leningrad (now reverted to its pre-1914 name of St Petersburg) was surrounded by German forces in 1941 and cut off from the rest of Russia. It was besieged for nearly three years, the great city’s population suffering terribly in the bitter cold of the Russian winter. Over a million men, women and children died of starvation and hypothermia, but the city fought on and never surrendered. In 1943 the Russian army broke through to link up with the garrison and end the longest, bloodiest siege of the Second World War.