Veleka River rises in Turkey, crosses the Bulgarian border, then flows through Southeast Bulgaria and completes its long and fascinating journey into the Black Sea. Veleka’s mouth is among nature's most painstaking and exquisite creations found on the Black Sea coast. A volcanic estuary with steep and rugged shores is formed into the river valley. The river flows into a scenic lagoon and then it dissipates into the sea beneath a nearly 500 m. long sandspit. The fascinating long and narrow slit in the sand spit, whence the river flows straight into the sea, adds the finishing touch to the dreamlike landscape.

Seen from a height, the mouth of Veleka River looks absolutely surreal. The nearby town of Sinemorets is a small and quiet place on the beach and the usual starting point for various hiking trails leading into the inland.

The area surrounding the Veleka River also boasts remarkable diversity in plant and animal life. A vast amount of fish diversity can be found in the river system- more than 30 species of freshwater fish, including endangered species such as European Eel (Anguilla anguilla), Common Carp (Cyprinus carpio), etc. The plant life includes rare species such as: the endangered yellow water-lily (Nuphar lutea), summer snowflake (or Loddon lily), sea carrot, morning glory (Calystegia soldanella) and others; the shores are covered in alder (Genus Alnus) and bamboo. Owing to this incredible natural wealth, the mouth of Veleka River was declared a protected area. “Veleka River Mouth “Protected Area is part of Nature Park "Strandzha". "Silkosia" and "Uzunbudzhak" Reserves are situated along the river as well.