The corner south-eastern tower with a circular cross-section is 46 meters high. It was built in 1488 according to the design of Marco Ruffo (Mark Fryazin) at the junction of the Moscow River with the moat that protected the wall from Red Square. By the way, this is the only tower built by Mark Ruffo without the participation of his colleagues. The name of the tower comes from the name of the boyar I.N. Beklemishev, whose yard was located nearby. Beklemishev was in power during the time of Ivan III, but fell out of favor with his son Vasily III and was executed in 1525. After the execution of the boyar, both the courtyard and the tower became the traditional place of detention for disgraced boyars. The tower was built to protect the crossing of the Moscow River and has a number of military devices, including three tiers of loopholes and a battle platform with machicolles (hinged loopholes) in the upper tier. The octagonal tent was added in 1680, but this is one of the few serious alterations that befell the tower.