WBelasica, Belles or Kerkini, is a mountain range in the region of Macedonia in Southeastern Europe, shared by northeastern Greece, southeastern North Macedonia (35%) and southwestern Bulgaria (20%).
WThe Dospat is a river in the Western Rhodope Mountains, the most important tributary of the Mesta.
WThe Erythropotamos or Luda reka is a river in southern Bulgaria and northeastern Greece. Its Turkish name was Kızıldelisu. Its source is near Mega Dereio. It flows into the Maritsa (Evros) near Didymoteicho.
WMaritsa, also known as Meriç or Evros, is a river that runs through the Balkans in Southeast Europe. With a length of 480 km (300 mi), it is the longest river of those that flow directly into the World Ocean and run solely in the interior of the Balkan peninsula, and one of the largest in Europe by discharge. It originates in Rila mountain and flows through Bulgaria in its upper and middle reaches, while its lower course forms much of the border between Greece and Turkey. Its drainage area is about 53,000 km2 (20,000 sq mi), of which 66.2% is in Bulgaria, 27.5% in Turkey and 6.3% in Greece. It is the main river of the historical region of Thrace, most of which lies in its drainage basin.
WRadomir or Kerkini, is a mountain on the Bulgarian–Greek border. At 2,031 metres (6,663 ft) it is the highest peak in the Belasica range. It is also known by its earlier Greek name Kalabáka.
WThe Rhodopes are a mountain range in Southeastern Europe, with over 83% of its area in southern Bulgaria and the remainder in Greece. Golyam Perelik is its highest peak at 2,191 meters (7,188 ft). The mountain range gives its name to the terrestrial ecoregion Rodope montane mixed forests that belongs in the temperate broadleaf and mixed forests biome and the Palearctic realm. The region is particularly notable for its karst areas with their deep river gorges, large caves and specific sculptured forms, such as the Trigrad Gorge.
WSlavyanka or Orvilos, formerly known as Alibotush and Kitka Planina, is a mountain located on the border of southwestern Bulgaria and northernmost Greece, located south of the Pirin Mountains and connected with it by the Paril Saddle. The highest peak of Slavyanka is Gotsev Vrah at 2,212 m, while other notable peaks include Golyam Tsarev Vrah, Malak Tsarev Vrah, Shabran and Salyuva Dzhamiya. The Bulgarian section of the mountain is part of the Ali Botush Reserve.
WStargach is a border mountain, situated between Bulgaria and Greece. It is located east of the Slavyanka Mountain, west of the Beslen hill, south of the Pirin Mountains and north of the Kato Novrokopi valley.
WThe Treaty of Neuilly-sur-Seine required Bulgaria to cede various territories, after Bulgaria had been one of the Central Powers defeated in World War I. The treaty was signed on 27 November 1919 at Neuilly-sur-Seine, France.
WTumba is a peak in the Belasica mountains in the region of Macedonia. The peak, 1,880 metres (6,170 ft) in height, lies on Belasica's main ridge, west of Lozen Peak and east of Sechena Skala Peak. A dome-shaped mountain with steep southern and northern slopes, Tumba is covered with low subalpine vegetation and is made of metamorphic rock. Tumba is notable as the point where the national borders of Bulgaria, Greece and North Macedonia meet (tripoint). It is one of the southwesternmost point of Bulgaria and one of the southeasternmost point of North Macedonia.