Manar Jonban
Coordinates: 32°39′1.65″N 51°35′39.11″E / 32.6504583°N 51.5941972°E
The Monar Jonban (Shaking Minarets), or Menar-e-jomban, is a monument located in Isfahan, in central Iran. Construction began in the 14th century to cover the grave of Amu Abdollah Soqla. Its notable feature is that if one of the minarets is shaken, the other minaret will shake as well.
The iwan (eyvān) and porch were probably erected shortly after 1316 as a shrine for Amu Abdollah Soqla, a hermit buried here. The brick minarets were constructed later, and are probably of Safavid dynasty era origin (c. 15th–17th centuries).
The iwan is 10 metres (33 ft) high and 10 metres (33 ft) in width, the minarets are 7 metres (23 ft) taller and are 4 metres (13 ft) in circumference. The roof above the shrine contains some skilled brickwork.
The minarets are responsible for the fame of the otherwise architecturally unremarkable shrine. Because of the ratio between the height and width of the minarets and the width of the iwan, if one minaret is shaken, the other will shake in unison. This example of coupled oscillation can be observed from ground level.
The wooden beams on the upper part of the minarets have been placed there to facilitate the shaking of the minarets, but the presence of wood in the brickwork causes other complications. The repeated shaking has been responsible for considerable structural damage.
Shaking by visitors is in theory restricted to once every twenty minutes. However, particularly during holidays, there is a constant stream of people who experiment with the phenomenon. The damage is locally believed by some to have been incurred during the periods of occupation by British soldiers.
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