# data[].attributes.location_name
Colosseum, Piazza del Colosseo, Rome, Metropolitan City of Rome Capital, Italy

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Colosseum was built over 2,000 years ago as a gift to the Roman people. It was a place for entertainment and battle. It is the largest ancient amphitheatre ever built.

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Eiffel Tower, Avenue Anatole France, Paris, France

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The Eiffel Tower was made in 1887 out of iron. When the tower opened in the 19th century, it was the world's tallest building at 1,024 feet. It is the most visited monument that you have to pay for in the world.

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The Palace of Westminster was destroyed in a catastrophic fire in 1834 and parliament decided that they would build a new clock tower as part of the restoration works. They started building the tower in 1843 and finished in 1859. Big Ben is 316 feet tall

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Leaning Tower of Pisa, Piazza del Duomo, Pisa, Province of Pisa, Italy

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Leaning Tower of Pisa, Piazza del Duomo, Pisa, Province of Pisa, Italy

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Leaning Tower of Pisa, Piazza del Duomo, Pisa, Province of Pisa, Italy

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The Leaning Tower of Pisa is known by most and no one understands how it is still standing. It was built in 1173 and was meant to stand 185 feet tall. The building is made of white marble. It is located in Pisa, Italy.

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This article was most recently revised and updated by

Leaning Tower of Pisa, Italian Torre Pendente di Pisa, medieval structure in Pisa, Italy, that is famous for the settling of its foundations, which caused it to lean 5.5 degrees (about 15 feet [4.5 metres]) from the perpendicular in the late 20th century. Extensive work was subsequently done to straighten the tower, and its lean was ultimately reduced to less than 4.0 degrees.

What is the Leaning Tower of Pisa?

Where is the Leaning Tower of Pisa located?

Why was the Leaning Tower of Pisa built?

When did the Leaning Tower of Pisa start leaning?

What efforts have been made to ensure the Leaning Tower of Pisa stays up?

The bell tower, begun in 1173 as the third and final structure of the city's cathedral complex, was designed to stand 185 feet (56 metres) high and was constructed of white marble. Three of its eight stories had been completed when the uneven settling of the building's foundations in the soft ground became noticeable. At that time, war broke out between the Italian city-states, and construction was halted for almost a century. This pause allowed the tower's foundation to settle and likely prevented its early collapse.

Giovanni di Simone, the engineer in charge when construction resumed, sought to compensate for the lean by making the new stories slightly taller on the short side, but the extra masonry caused the structure to sink still further. The project was plagued with interruptions, as engineers sought solutions to the leaning problem, but the tower was ultimately topped out in the 14th century. Twin spiral staircases lined the tower's interior, with 294 steps leading from the ground to the bell chamber (one staircase incorporates two additional steps to compensate for the tower's lean). Over the next four centuries the tower's seven bells were installed; the largest weighed more than 3,600 kg (nearly 8,000 pounds). By the early 20th century, however, the heavier bells were silenced, as it was believed that their movement could potentially worsen the tower's lean.

The foundations have been strengthened by the injection of cement grout and various types of bracing and reinforcement, but in the late 20th century the structure was still subsiding, at the rate of 0.05 inch (1.2 mm) per year, and was in danger of collapse. In 1990 the tower was closed and all the bells silenced as engineers undertook a major straightening project. Earth was siphoned from underneath the foundations, decreasing the lean by 17 inches (44 cm) to 13.5 feet (4.1 metres); the work was completed in May 2001, and the structure was reopened to visitors. The tower continued to straighten without further excavation, until in May 2008 sensors showed that the motion had finally stopped, at a total improvement of 19 inches (48 cm). Engineers expected the tower to remain stable for at least 200 years.

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Kathleen Sheetz.

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gravity: The principle of equivalence

...of dropping objects from the Leaning Tower of Pisa has been reproduced in the laboratory with apparatuses used to determine the absolute value of gravity by timing a falling body. Two objects, one of uranium, the other of copper, were timed as they fell. No difference was detected....

Galileo: Early life and career

...the top of the famous Leaning Tower, that the speed of fall of a heavy object is not proportional to its weight, as Aristotle had claimed. The manuscript tract De motu ( On Motion), finished during this period, shows that Galileo was abandoning Aristotelian notions about motion and was instead taking...

...cathedral, baptistery, and campanile (the leaning tower). The cathedral and the baptistery were decorated by a succession of distinguished sculptors, including Guglielmo Pisano, Bonanno Pisano, Nicola Pisano, and Nicola's son Giovanni Pisano....

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Leaning Tower of Pisa | tower, Pisa, Italy

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Leaning Tower of Pisa, medieval structure in Pisa, Italy, that is famous for the settling of its foundations, which caused it to lean 5.5 degrees (about 15 feet [4.5 metres]) from the perpendicular in the late 20th century. Extensive work was subsequently done to straighten the tower, and its lean

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Almudena Cathedral, Calle de Bailén, Madrid, Spain

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Almudena Cathedral, Calle de Bailén, Madrid, Spain

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Almudena Cathedral, Calle de Bailén, Madrid, Spain

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The cathedral was put into place by Pope John Paul II on 15 June 1993. Alfonso XII of Spain began the construction of la Almudena began on 4 April 1883.

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Almudena Cathedral, Calle de Bailén, Madrid, Spain

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St. Basil's Cathedral, Red Square, Moscow, Russia

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St. Basil's Cathedral, Red Square, Moscow, Russia

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St. Basil's Cathedral, Red Square, Moscow, Russia

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St. Basil's Cathedral was built between 1554 and 1560. Saint Basil the Great was known to be "idiotic for Christ's sake". He was buried in the church's vaults between 1584-1598. The landmark is one of the most known landmarks in Russia.

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Saint Basil the Blessed, also called Pokrovsky Cathedral, Russian Svyatoy Vasily Blazhenny or Pokrovsky Sobor, church constructed on Red Square in Moscow between 1554 and 1560 by Tsar Ivan IV (the Terrible), as a votive offering for his military victories over the khanates of Kazan and Astrakhan. The church was dedicated to the protection and intercession of the Virgin, but it came to be known as the Cathedral of Vasily Blazhenny (St. Basil the Beatified) after Basil, the Russian holy fool who was "idiotic for Christ's sake" and who was buried in the church vaults during the reign (1584-98) of Tsar Fyodor I.

K. Scholz/H. Armstrong Roberts

The church was designed by two Russian architects, Posnik and Barma (who may in fact have been one person). According to popular legend, however, it was built by an Italian architect who was blinded so that he could never create anything that was similar or equal.

© AbleStock.com/Jupiterimages

J.E. Luebering, Executive Editorial Director.

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Saint Basil the Blessed | church, Moscow, Russia

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Saint Basil the Blessed, church constructed on Red Square in Moscow between 1554 and 1560 by Tsar Ivan IV (the Terrible), as a votive offering for his military victories over the khanates of Kazan and Astrakhan.

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Prague Castle, Hradčany, Prague 1, Czechia

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Prague Castle, Hradčany, Prague 1, Czechia

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Prague Castle, Hradčany, Prague 1, Czechia

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The castle was built in the 9th century and has been home to countless kings and queens. It is 70,000 square miles large.The castle is one of the most visited tourist attractions in Prague with 1.8 million people visit per year.

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Ukrainian Motherland Monument, Lavrska Street, Kyiv, Ukraine

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Ukrainian Motherland Monument, Lavrska Street, Kyiv, Ukraine

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Ukrainian Motherland Monument, Lavrska Street, Kyiv, Ukraine

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The Ukrainian Motherland Monument was opened on May 9, 1981. The statue is made of pure titanium and is 203 feet tall. The monument weights 560,000 lbs. The statue is meant to show the resilience of the Ukrainian people. The statue is one of the most visited tourist attractions in Ukraine.

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Binbirdirek, The Blue Mosque, At Meydanı Cd, Fatih/İstanbul, Türkiye

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Binbirdirek, The Blue Mosque, At Meydanı Cd, Fatih/İstanbul, Türkiye

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Binbirdirek, The Blue Mosque, At Meydanı Cd, Fatih/İstanbul, Türkiye

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The Blue Mosque was built between 1609 and 1617. The monument still remains a functional mosque today and is one of the most beautiful mosques in the world. It is one of the most popular monuments of the Ottoman Empire.

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The Royal Palace, Slottsplassen, Oslo, Norway

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The Royal Palace, Slottsplassen, Oslo, Norway

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The Royal Palace, Slottsplassen, Oslo, Norway

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The Norwegian Royal Palace was started on october 1st, 1825 and was finished in 1849. It was meant to house King Carl Jonah but it was finished after his death. The palace is a massive tourist attraction because they do guided tours through it.

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The Royal Palace, Slottsplassen, Oslo, Norway