The Troitskaya (Trinity) Tower, built in 1495, was regarded as the second most significant tower of the Kremlin after the Spasskaya. It consists of six square tiers. Under the tower was the two-level basement, which served for defense purposes, and later, in the 15th – 16th centuries was used as a prison. Troitskaya tower Gate was especially honored; it was used by empresses and princesses as well as the Patriarch. Through the gates the clergy came out to meet the tsar returning from wars. The modern name, Troitskaya (Trinity) was given to the tower in 1658 after the Trinity monastery in the Kremlin.
In 1686 the tower was decorated with two-headed eagle and the clock, however, during the fire of 1812 they were completely destroyed and rebuilt only in the late twentieth century. In 1935, the dome of Troitskaya Tower, as well as other domes of the Kremlin's towers lost their double-headed eagles, which were replaced with five-pointed stars. The star of the Troitskaya Tower is the most massive; its weight is about 1.5 tons. In 1985 the tower was heightened with decorated multi-tier top. Troitskaya Tower is the highest tower of the Kremlin, its height with the star (from the side of Alexander Garden) is 80 m.