The southern border is 752 km long, of them 259 km are with Turkey and 493 km are with Greece. The Bulgaria–Turkey frontier runs from the mouth of the Rezovo River in the east through the Strandzha Mountains and the Dervent Heights, crosses the river Tundzha at the village of Matochina and ends at the river Maritsa at the village of Kapitan Andreevo. There are three border crossings at Malko Tarnovo, Lesovo and Kapitan Andreevo. The border with Greece runs from Kapitan Andreevo through several ridges of the Rhodope Mountains, generally following the watershed of the rivers Arda and Vacha on the Bulgarian side, runs through the Slavyanka Mountain, crosses the river Struma at the village of Kulata and runs through the crest of the Belasitsa Mountain to the Tumba Peak. There are six border checkpoints at Svilengrad, Ivaylovgrad, Makaza, Zlatograd, Ilinden and Kulata.