See a learned dissertation of Baier, de muro Caucaseo, in Comment. Acad. Petropol. ann. 1726, tom. i. p. 425 - 463; but it is destitute of a map or plan. When the czar Peter I. became master of Derbend in the year 1722, the measure of the wall was found to be 3285 Russian orgygiae, or fathom, each of seven feet English; in the whole somewhat more than four miles in length.