‘Without this river the Russians could not live,’ remarked Robert Bremner in his work, Excursions in the Interior of Russia. The year is 1840. The river in question, the Volga, the 2,000 mile-long meandering waterway stretching from the forests of north-west Russia to the steppes by the Caspian. At the time of Bremner’s survey, half of the Russian empire’s fish was caught in the single stretch of river by Astrakhan, the Volga’s final pit stop before flowing out to sea.