With the exception of some pockets of overdevelopment, the northern Bulgarian Black Sea coast remains a place of relatively unspoiled nature, picturesque beaches and cliffs, historical sites and landscapes to remember. It is the home of rare ecosystems, like the easternmost edges of the great Eurasian steppes. Its location on the Via Pontica migratory route is why in spring and autumn its skies are full with birds, many of them endangered species.
The result of centuries of violent storms embedded in the consciousness of seafaring nations, the name of the Black Sea should not be taken literally. Its waters are not black, but mainly dark blue or lead grey, depending on the weather and the season.
Yet in June the Black Sea turns a vivid green, a colour you'd expect to see at an exotic tropical beach. Last year the change was so dramatic that it was visible from space. A NASA composite satellite photo showed the Black Sea's deep blue heart covered with swirls of turquoise.
How does this happen?
