The Mesta River is a significant waterway located in southeastern Europe, primarily flowing through Greece and Bulgaria. It originates from the Rila Mountains in Bulgaria and travels approximately 130 kilometers before emptying into the Aegean Sea. The river is known for its picturesque landscapes and rich biodiversity. The Mesta River basin supports various ecosystems and is vital for local agriculture and irrigation. It also serves as a natural border between Greece and Bulgaria in some areas. The river is popular for recreational activities such as fishing and kayaking, attracting both locals and tourists.