The history, Tarikh Bulgar, said to have been written in the 12th century by an Arabian cadi of the city Bolgari, has not yet been discovered; but the Arabian historians, Ibn Foslan, Ibn Haukal, Abul Hamid Andalusi, Abu Abdallah Harnati, and several others, who had visited the kingdom, beginning with the 10th century, have left descriptions of it.
Davis also reported, but did not see, a similar inscription at Bulgar Maden, not far away.
Subsequent Bulgarian operations were confined to resisting Turkish attempts to advance from Chatalja; to the occupation of Thrace down to the Sea of Marmora; to resisting an attack on the Bulgar lines across the isthmus of the Gallipoli Peninsula; and to the capture of Adrianople.
It attains in Lycia an altitude of 10,500 ft., and in the Bulgar Dagh (Cilicia) of over 10,000 ft.
East of the Bulgar Dagh the range is pierced by the Sihun and Jihun rivers, and their tributaries, but its continuity is not broken.