Where exactly is the Black Sea? It is formed by three rivers: the Danube, the Dnieper and the River Don and is bordered by six countries: Romania, Bulgaria, Turkey, Georgia, Russia and Ukraine. The population of the greater Black Sea basin is more than 160 million.

Nobody really knows why the Black Sea is called such. Some say that it gained its name from sailors and pirates who were struck by its dark appearance when the sky turned black with storm clouds. The Ancient Greeks called the Black Sea the Scythian Sea, after the not so friendly tribes who lived on its shores at the time. Shipwrecked sailors could generally expect no a hard time from the Scythians, who raided the wrecks and were said to have made wine goblets out of sailors’ skulls. The Greeks also called it Pontos Axenos – the inhospitable sea – until they settled in Crimea, after which they changed their minds and called it Pontos Euxenos: the hospitable sea.

The Black Sea is very deep (1,271m at the centre) but it’s less salty than most oceans. It began life as a fresh water lake about 22,000 years ago. About 7,000 – 9,000 years ago, global warming melted glaciers and the polar ice-caps, sea levels rose and eventually the Mediterranean overflowed through the Bosporus, turning the lake into the Black Sea. Many archaeologists think that this catastrophic event was in fact the Noah’s Flood of the Bible.

The sea is unique in having two layers, an oxygenated upper layer, about 200m deep, with fish life, and a `dead’ lower layer, where until recently nothing was thought to be able to survive.

A peculiarity of the Black Sea is the bi-directional current where it flows through the Bosporus straits on its way to the Mediterranean. The surface current flows westwards through the straits into the Sea of Marmaris, but there is a deep current which flows simultaneously in the opposite direction, back into the Black Sea.

There are plenty of beaches in The Crimea, of Florence Nightingale fame – some 517 km of beaches – mostly small pebbles and some black volcanic sand. Many beaches are public, and the private ones owned by hotels and sanatoria are usually open to non-patrons at a price of around 3 Hryvnias (£0.40p or $0.56 cents) per day. There are also naturist beaches near Koktebel in the east.