Kalyazin is one of the oldest towns on the Volga River, and is now known primarily for its unusual attraction — the Flooded Bell Tower. The tower is all that is left of Kalyazin's Trinity Monastery. The monastery was famous from the XII century onwards under the name of Nicholas on Jabnya, but in the early XVII century, the so-called Time of Troubles left their mark on the monastery, damaging it severely.

It was, however, rebuilt from 1633—1654 and became one of the largest monasteries in Tver region.

After the Revolution of 1917, the monastery was closed down and served the needs of different organizations, also hosting a local historical museum. The construction of the Uglich hydro-electric power station and of the Uglich reservoir from 1936 to 1940 caused many architectural and historical buildings to be flooded, including the monastery at Kalyazin.

All that is left now is the Bell Tower of St. Nicholas Cathedral. It was built from 1796 to 1800 by three local serf craftsmen from Kalyazin: Vassiliy Ushakov, Evdokim Ivanov and Ivan Rudelev. The belfry had 12 bells, the largest of which, weighing 1038 poods (old Russian measurement, the equivalent of approx. 17 000 kilograms), was casted at the monastery’s expense in 1895 in commemoration of Nicholas II accession to the throne. The Bell Tower was 74 meters high and has four tiers; originally, however, it had five tiers. At the moment the lower tier is underwater. There is a legend that the Bell Tower was used as a lighthouse at first, but when the bells were being removed, the biggest one crashed onto the wooden platform beneath it. The platform could not resist its weight and collapsed, taking with it all the other floors right down to the basement. Since a flood was expected, the workers decided not to take the bell away. By the summer, when the flood had receded, the basement remained flooded. The bell was in the basement, so the idea to use the tower as a lighthouse was never realised. However, at the beginning of 1941 the bell started ringing, and during the night of the 22nd of June when the Great Patriotic War broke out, people heard the bell ringing an alarm signal.