Located at a source Orel'. Primary name Troitskaia. In 1738 renamed on the name Yefremovskii equestrian regiment, placed on this area of line. A fortress earthen, rectangular in a plan, is fourbastion, entrance - in north-western curtain. The area of fortress court more than 1,5 ha, in a center is track of well. Strengthening has considerable damages. The extent of fortress on exteriority of founding of billow is made by a more than 1040 m Fortress is surrounded by a wide ditch, in course of time growing into shallow. South-east curtain is increased by a ravelin, directed toward Orel'. A billow which Yefremovskaia a fortress was connected with fifth on the line of Alekseevskaia and seventh was saved - Paraskevskaia.