From 2016 Kokui Tower is closed until the end of the repair works.

The tallest Kremlin tower is Kokui Watchtower (41 meters). It was built in the 17th century. Its peculiar shape and height make it different from other towers.

In the 19th century the firefighters of the Sofia side of the city kept pigs and stored cabbage in the lower part of the tower.

During World War II the tower served as a German observation post. By the time the city was liberated in 1944 the upper part of the tower was severely damaged by a bomb. In 1960s the 17th-century shape of the tower was restored according to the A. Vorobiev project.

There is an observation deck in the tower where one can admire the Prince’s, Saviour and Palace towers and St. George's (Yuriev) Monastery. The 5 ruble note depicted the view from the tower. In 2012 there were two telescopes with 60x zoom installed at the observation deck.