The Bulgarian Black Sea Coast

Bulgaria’s 378-km-long, picturesque Black Sea coastline is dotted with beaches of golden sand, river valleys, estuaries and ancient towns. It is the most important tourist destination of the country during the summer season, attracting millions of foreign and local tourists every year. The Bulgarian Riviera, as it is often referred to, has more than 130 km of sandy beaches and dozens of sea resorts.

Sandy beach at the Black Sea in Bulgaria

The Black Sea is an ideal summer holiday destination even with small children because of its calm waters, soft sand and relatively shallow beaches. It is also an incredible combination of rich history, wonderful location, unique natural and climatic conditions and beautiful settlements.

The summer season starts in late May and lasts until early October. With more than 300 hours of monthly sunshine in July and August, the average summer air temperature is about 28 °C, while water temperature averages at 26 °C. The sea surface is warmest in August when the water can reach a temperature of 29 °С.

The European Environment Agency (EEA) assesses the bathing water quality in all the EU Member States every year. According to their latest report, all the beaches in Bulgaria had at least sufficient water quality in 2019, 65% of them tested as ‘Excellent’.

Bulgaria’s third and fourth largest cities, Varna and Burgas respectively, are the main hubs of the coastal region. Their international airports serve as the gateway to the Black Sea for most of the foreign visitors.

Resorts and sights

The Black Sea

The color of the Black Sea varies from dark blue to greenish-blue, even yellowish at river mouths, but it never turns black. But why is it called Black Sea then? The most plausible theory is that the name refers to a stormy and dangerous sea for shipping. Nonetheless, the Black Sea is a very calm body of water. The tides are insignificant (3-8 cm), which is due to its small size and remoteness from the oceans. The maximum wave height does not exceed 5-6 m, the average annual wave height in Varna Bay is 31 cm. The calmest months, in which there are almost no waves higher than 1 m, are May, June and July.

The Black Sea has a beneficial effect on the climate of the Bulgarian coast. The warm sea water heated during the summer continues to emit heat, thus raising air temperature. Because of this, autumns at the Bulgarian coast are pleasant, very clear, sunny and warm.

The Black Sea in Nesebar
The Black Sea in Nesebar

Large European rivers as the Danube, Dnieper, Southern Bug, Dniester, Don and many others drain into the Black Sea. From these rivers, together with the precipitation, the sea receives much more freshwater per year than the amount of water lost by evaporation. Excess water drains through the Bosporus and the Dardanelles into the Mediterranean. If this connection did not exist, the sea level would rise by about 1 m annually.

Due to the large inflow of freshwater, the salinity of the Black Sea is significantly lower than many other seas. While the salinity of the Mediterranean is averaging 38 PSU, the salinity of the Black Sea surface waters is less than half of that, only 17 PSU. In its northwestern part, where the larger rivers flow into it, the salinity can drop even to 13 PSU.

An interesting feature of the Black Sea is the presence of large amounts of hydrogen sulfide, which is believed to be produced by sulfur reducing bacteria in the lower layers of its waters. It appears at a depth of 150-200 m where an oxygen – hydrogen sulfide interface is established, after which the concentration of hydrogen sulfide starts increasing and anoxic conditions exist. This does not allow the presence of life, therefore all marine life accumulates in the upper layers of the sea.

There are about 600 species of plants and about 1520 animal species living in the Black Sea. Among others, it accommodates the zebra mussel, common carp, anchovies, horse mackerel, hermit crab, stingrays, jellyfish, tuna and seahorse. Three species of dolphins also live here: the common dolphin, the bottlenose dolphin and the harbour porpoise.

There is a species of shark inhabiting the sea, the spiny dogfish or mud shark, which is small (80-160 cm) and not dangerous to humans. There are only two potentially harmful species along the shores: the greater weever (called sea dragon in Bulgarian) and the sea urchin, which have poisonous spines. The contact with these is very painful, but not deadly at all.

Bulgarian seaside at Sinemorets

An important advantage of the Bulgarian Black Sea coast is the practically inexhaustible amount of healing mud. The natural mud-healing method, which has both medical and economic potential, is rapidly gaining international recognition and popularity. Currently, most of the many spas around the coast offer mud therapy service.

Another remedy with strong healing potential and in unlimited quantities along the coast is sea lye, an oil-like liquid, produced by evaporating saltwater. Its application is recommended for rheumatic and neurological illnesses, joint pain, injuries, external wounds and ulcers. Sea lye is also anti-inflammatory and antiseptic.