The popularity of the Bulgarian coast and sea resorts has seen a robust growth in recent years, following the fall of communism and the opening of borders to foreign tourists. The tourism industry has grown into one of the main drivers of the national economy with double-digit growth rates of the number of tourists each and every year. Bulgaria offers a budget alternative to more expensive European resorts, while quality of service does not fall behind Western European standards in high-class resorts such as Albena, Golden Sands, Sunny Beach, Duni or the local Riviera holiday club. White and tender sands and warm waters from June to September go together with a marvelous nature and hundreds of places of interest along the coast, ranging from old pagan sanctuaries to remains of ancient Roman and Greek civilisations, and authentic cultural and historical monuments of the Bulgarian state.
source - http://www.bulgariansearesorts.com/

South Black sea coast
Due to the unique combination of marvelous sand stripes, crystal sea, and beautiful forests, cut by picturesque rivers the region of South Black Sea Coast offers wonderful opportunities for sea and ecological tourism.
   There are situated numerous reserves that keep the bio diversity of the region. The reserve of Ropotamo, located at the lower course of the river of the same name is famous for the beautiful water lilies that grow there and one of the most whimsical rock formations in the country known as the Lion's head. It includes several smaller reserves and parks that preserve unique flora, fauna and natural landmarks. They are the natural park Ropotamo, the reserves of Arkutino, Zmiiski ostrov (Snake's Island) and Morski pelin. Other reserves in the region are Alepou - a swampy lagoon which hosts a plethora of resident and migratory fauna and Pyasachnite lilii (The Sandy lilies).
   The South Black Sea Coast offers opportunities for sea vacations for every one's taste. Those looking for luxury and first class comfort should go to resort of Dyuni and the town of Sozopol and those who want quiet and rest should go to Chernomorets, Primorsko, Kiten, Lozenets, Ahtopol, Sinemorets.

source - http://www.bgglobe.net