Slavyanka, Cross-border mountain between Bulgaria and Greece.

Slavyanka, also called Alibotush in Bulgarian and Orvilos in Greek, is a mountain on the Bulgaria–Greece border, south of Pirin and linked to it by the Paril saddle. It is a horst built mainly of massive and banded marbles over a granite core, about 20 km long and 10–12 km wide. Its highest point, Gotsev Vrah (2,212.6 m), lies on the border between boundary pyramids No. 99 and No. 100.

Herodotus in the 5th century BC and Arrian in the 2nd century AD mention the mountain as Orbelos, the latter in the account of Alexander the Great's campaign against the Triballi. The name Alibotush was officially changed to Slavyanka by state decree on 23 November 1951, though locals still use the old name. In 1933 naturalist Alexander Dryanovski proposed the name Kitka for its rich flora.

The name Alibotush, still used by locals, may derive from the personal name Libota with the suffix -ush, as in Dragush from Dragota. A legend tells of the haiduk voivode Ilia, called Ali the Terrible by the Ottomans, who climbed the peak in boots filled with hot pitch and died there. In Greece the mountain is called Orvilos, after the ancient Orbelos.

Access is difficult because there is no road network on the mountain. The summit, Gotsev Vrah (2,212.6 m), lies on the border between boundary pyramids No. 99 and 100; from the Greek side it can be climbed from Kato Vrontou (Karakioi, 760 m) in about 3:30 hours, or from a point on the road at 1,200 m north of Achladokastro (Krushevo) in about 2:30 hours.

The mountain's highest point, Gotsev Vrah (2,212.6 m), sits exactly on the border between boundary pyramids No. 99 and 100. On the Greek side it is called Tsolias. The summit can be reached from the village of Kato Vrontou area: about 3:30 hours from Karakioi (Katafyto, 760 m) or 2:30 hours from a point on the road at 1,200 m north of Achladokastro (Krushevo).