The Leaning Tower of Nevyansk (Russian: Невья́нская ба́шня) is a tower in the town of Nevyansk in Sverdlovsk Oblast, Russia, built in the 18th century. Its construction was funded by the blacksmith and industrialist Nikita Demidov and later his son Akinfiy Demidov, a famous Russian manufacturer and an associate of Peter the Great.

This article has multiple issues. Please help improve it or discuss these issues on the talk page. (Learn how and when to remove these template messages) This article's tone or style may not reflect the encyclopedic tone used on Wikipedia. (April 2012) This article possibly contains original research. (April 2012) This article needs additional citations for verification. (March 2015)

The height of the tower is 57.5 metres (189 ft).^[1] The base is 9.5 metres (31 ft) wide. The deviation of the top part of the tower, from the vertical, is about 3 degrees. The exact date of construction is unknown, but Russian historians believe that it was built between 1721 and 1745.^{[citation needed]} The architect is unknown.

Following the restoration, the Nevyansk Tower was opened to the public. Guided tours are provided by a local museum and tourist guides from Yekaterinburg.

The Leaning tower is featured on Nevyansk's flag and coat of arms.^[2]

• The base is a square with sides of 9.5 metres.
• Vertical deviation of the tower is about 1.85 metres.
• Secular sediment is 0.9 millimetres per year.
• The height is 57.5 metres.
• The thickness of the walls is 2 metres at the base, 32 centimetres at the top level.
• The weathercock weighs 25 kilograms and is 178 centimetres long.
• The diameter of the ball-lightning rod is 30 centimetres; the length of the spike-ray is 40 centimetres.
• The musical chime has 10 copper bells and 1 bronze bell weighing more than a ton.^[3]

Historians still debate the built purpose of the Nevyansk Tower. It was likely meant to embody the might of the Demidov family and serve as an architectural symbol of their dynasty. It has been suggested that it was also used as a "bank safe", a watchtower, a belltower, prison,^[1] or a laboratory for conducting chemical experiments and producing counterfeit money.

During restoration work, archaeologists were able to determine the purpose of some of the rooms. The second floor may have been Demidov’s office, where he kept his archives and other papers. The third floor housed a laboratory, equipped with a furnace. A soot sample taken from the flue, showed traces of silver and gold, which some consider might relate to a theory, later refuted by scientists, that the Demidov's may have been conducting coin minting activity there. The tower could have been used for smelting the top layers of ore-bearing deposits, which often contain silver or gold. Floors four to six have only stairwells. The seventh and the eight floors house a clock that plays music on a carillon made by the English master Richard Phelps in 1730.

It is said that the clock was purchased by Demidov for 5,000 rubles, a considerable amount for that time. To compare, the construction of the Nevyansk Tower itself, costed 4,207 rubles. The clock has three dials, ten music bells, weighing about four tons, and one alarm bell. The ninth floor was believed to be used as an observation post.

The purpose of one particular room in the tower is still debated. Archaeologists dubbed it the "acoustic room." It measures 20 square metres (220 sq ft) and is located between the fourth and the fifth floors. A person standing in one corner of this room can whisper words to another person in the opposite corner and they will be readily audible. Researchers do not know whether the room was built this way on purpose or not. It could be that Demidov used this acoustic room for gathering intelligence on his high-ranking guests.

The reason of the tower's inclination is surrounded by legends. One of them claims that the tower was purposely inclined to face southwest in the direction of Demidov’s birthplace^[1] in Tula. Another legend claims that once the construction of the tower had been completed, Akinfiy Demidov and the architect, went on top of the tower where Demidov asked him whether he could build anything better than the Nevyansk Tower. The architect answered "yes" and Demidov ordered him thrown from the top of the building (a similar legend is attached to the construction of the Prague Astronomical Clock). The next morning, the locals supposedly noticed that the tower had leaned forward a bit and water had started trickling down the walls. One can see water constantly dripping down the southwest wall of the tower to this day (albeit as a result of a natural phenomenon).

The restorers say that there is no evidence to assume that the Nevyansk Tower was purposely built inclined.^[1] The current surveying data shows that the defect had to be obvious during the construction. It appears that drifting grounds were to blame for the inclination of the tower from the very beginning. Scientists believe that an uneven subsidence took place when the tower had already been partially built. Most likely, the construction workers stopped building the tower on seeing the defect, but later on they decided to go on with their work. This is supported by the color of mortar between the bricks, the composition of which changed as the builders worked their way up. Specially trimmed bricks were used to even out the tower.^[1] Current measurements indicate that there is a 3-degree deviation of the bases' tower from its axis, while the middle part is partially straightened as the inclination equals only one degree. The top part of the tower stands vertically.

Brick were constructed of fired clay that incorporated the colors of lime and egg white,^[3] the tower's tented roof was the first cast iron cupola in the world, consisting of a metal carcass and outer shell.^{[citation needed]} The second time this technique was applied, about 100 years later, was during the reconstruction of the Mainz Cathedral in Germany in 1826, and the third time it was used in the dome of Saint Isaac's Cathedral in St. Petersburg, built in the 1840s.

The top of the tower is crowned with a gilded sphere with spikes, built somewhere between 1721 and 1745. These were recently interpreted as lightning rods (existing 28 years before Benjamin Franklin's scientific explanation of such devices).

The structural parts of the tower were reinforced with wrought iron bars as well as cast iron elements.^{[citation needed]}

Wikimedia Commons has media related to Невьянская наклонная б́ашня.

• List of leaning towers