The Leaning Tower of Pisa ( it, torre pendente di Pisa), or simply, the Tower of Pisa (''torre di Pisa'' ), is the ''
campanile'', or freestanding bell tower, of
Pisa Cathedral
Pisa Cathedral ( it, Cattedrale Metropolitana Primaziale di Santa Maria Assunta; Duomo di Pisa) is a medieval Roman Catholic cathedral dedicated to the Assumption of the Virgin Mary, in the Piazza dei Miracoli in Pisa, Italy, the oldest of the t ...
. It is known for its nearly four-degree lean, the result of an unstable
foundation
Foundation may refer to:
* Foundation (nonprofit), a type of charitable organization
** Foundation (United States law), a type of charitable organization in the U.S.
** Private foundation, a charitable organization that, while serving a good cause ...
. The tower is one of three structures in the
Pisa's Cathedral Square (''
Piazza del Duomo''), which includes the cathedral and
Pisa Baptistry.
The height of the tower is from the ground on the low side and on the high side. The width of the walls at the base is . Its weight is estimated at . The tower has 296 or 294 steps; the seventh floor has two fewer steps on the north-facing staircase.
The tower began to lean during construction in the 12th century, due to soft ground which could not properly support the structure's weight. It worsened through the completion of construction in the 14th century. By 1990, the tilt had reached 5.5 degrees. The structure was stabilized by remedial work between 1993 and 2001, which reduced the tilt to 3.97 degrees.
Architect
There has been controversy surrounding the identity of the architect of the Leaning Tower of Pisa. For many years, the design was attributed to Guglielmo and
Bonanno Pisano, a well-known 12th-century resident artist of Pisa, known for his
bronze casting
Lost-wax casting (also called "investment casting", "precision casting", or ''cire perdue'' which has been adopted into English from the French, ) is the process by which a duplicate metal sculpture (often silver, gold, brass, or bronze) ...
, particularly in the
Pisa Duomo. Pisano left Pisa in 1185 for
Monreale, Sicily, only to come back and die in his home town. A piece of cast bearing his name was discovered at the foot of the tower in 1820, but this may be related to the bronze door in the façade of the cathedral that was destroyed in 1595. A 2001 study seems to indicate
Diotisalvi was the original architect, due to the time of construction and affinity with other Diotisalvi works, notably the bell tower of
San Nicola and the
Baptistery
In Christian architecture the baptistery or baptistry (Old French ''baptisterie''; Latin ''baptisterium''; Greek , 'bathing-place, baptistery', from , baptízein, 'to baptize') is the separate centrally planned structure surrounding the baptismal ...
, both in Pisa.
File:Leaning tower of Pisa - capital of column at the top.jpg, Column capital details on top level
File:Torre di pisa, capitello con scimmiette.JPG, Column details
File:Pisa. Torre 02.JPG, Base wall columns
File:Pisa, torre pendente (18).jpg, Flower pendant
File:Pisa. Torre 01.JPG, Entrance
File:Animals and monsters on the wall of the leaning tower of Pisa.jpg, Wall relief details of animals
File:Torre di Pisa - panoramio (18).jpg, Outer floor tiles
File:Leaning tower bell assunta.JPG, ''Assunta'' bell
File:Pisa Leaning Tower bell San Ranieri.jpg, ''Pasquareccia'' bell
File:Cos de campanes de la torre de Pisa.JPG, Top-level bells
Construction
Construction of the tower occurred in three stages over 199 years. On 5 January 1172, Donna Berta di Bernardo, a widow and resident of the house of dell'Opera di Santa Maria, bequeathed sixty
soldi to the . The sum was then used toward the purchase of a few stones which still form the base of the bell tower. On 9 August 1173, the foundations of the tower were laid.
Work on the ground floor of the white marble campanile began on 14 August of the same year during a period of military success and prosperity. This ground floor is a
blind arcade
A blind arcade or blank arcade is an arcade (a series of arches) that has no actual openings and that is applied to the surface of a wall as a decorative element: i.e., the arches are not windows or openings but are part of the masonry face. It is ...
articulated by engaged columns with classical
Corinthian capitals
The Corinthian order (Greek: Κορινθιακός ρυθμός, Latin: ''Ordo Corinthius'') is the last developed of the three principal classical orders of Ancient Greek architecture and Roman architecture. The other two are the Doric order w ...
. Nearly four centuries later
Giorgio Vasari
Giorgio Vasari (, also , ; 30 July 1511 – 27 June 1574) was an Italian Renaissance Master, who worked as a painter, architect, engineer, writer, and historian, who is best known for his work '' The Lives of the Most Excellent Painters, Sculp ...
wrote: "Guglielmo, according to what is being said, in the year 1174, together with sculptor Bonanno, laid the foundations of the bell tower of the cathedral in Pisa".
The tower began to sink after construction had progressed to the second floor in 1178. This was due to a mere three-metre foundation, set in weak, unstable
subsoil, a design that was flawed from the beginning. Construction was subsequently halted for almost a century, as the
Republic of Pisa
The Republic of Pisa ( it, Repubblica di Pisa) was an independent state centered on the Tuscan city of Pisa, which existed from the 11th to the 15th century. It rose to become an economic powerhouse, a commercial center whose merchants dominated ...
was almost continually engaged in battles with
Genoa
Genoa ( ; it, Genova ; lij, Zêna ). is the capital of the Italian region of Liguria and the sixth-largest city in Italy. In 2015, 594,733 people lived within the city's administrative limits. As of the 2011 Italian census, the Province of ...
,
Lucca
Lucca ( , ) is a city and ''comune'' in Tuscany, Central Italy, on the Serchio River, in a fertile plain near the Ligurian Sea. The city has a population of about 89,000, while its province has a population of 383,957.
Lucca is known as one ...
, and
Florence
Florence ( ; it, Firenze ) is a city in Central Italy and the capital city of the Tuscany Regions of Italy, region. It is the most populated city in Tuscany, with 383,083 inhabitants in 2016, and over 1,520,000 in its metropolitan area.Bilan ...
. This allowed time for the underlying soil to settle. Otherwise, the tower would almost certainly have toppled.
On 27 December 1233, the worker Benenato, son of Gerardo Bottici, oversaw the continuation of the tower's construction.
On 23 February 1260, Guido Speziale, son of
Giovanni Pisano
Giovanni Pisano (c. 1250 – c. 1315) was an Italian sculptor, painter and architect, who worked in the cities of Pisa, Siena and Pistoia. He is best known for his sculpture which shows the influence of both the French Gothic and the Ancient ...
, was elected to oversee the building of the tower. On 12 April 1264, the master builder
Giovanni di Simone Giovanni may refer to:
* Giovanni (name), an Italian male given name and surname
* Giovanni (meteorology), a Web interface for users to analyze NASA's gridded data
* ''Don Giovanni'', a 1787 opera by Wolfgang Amadeus Mozart, based on the legend of ...
, architect of the
Camposanto
Camposanto ( Modenese: ; Mirandolese: ) is a ''comune'' (municipality) in the Province of Modena in the Italian region Emilia-Romagna, located about northwest of Bologna and about northeast of Modena on the Panaro river. Although the name in ...
, and 23 workers went to the mountains close to Pisa to cut marble. The cut stones were given to Rainaldo Speziale, worker of St. Francesco. In 1272, construction resumed under Di Simone. In an effort to compensate for the tilt, the engineers built upper floors with one side taller than the other. Because of this, the tower is curved.
Construction was halted again in 1284 when the Pisans were defeated by the Genoese in the
Battle of Meloria
The Battle of Meloria was fought near the islet of Meloria in the Ligurian Sea on 5 and 6 August 1284 between the fleets of the Republics of Genoa and Pisa as part of the Genoese-Pisan War. The victory of Genoa and the destruction of the Pisan ...
.
The seventh floor was completed in 1319. The bell-chamber was finally added in 1372. It was built by
Tommaso di Andrea Pisano, who succeeded in harmonizing the
Gothic
Gothic or Gothics may refer to:
People and languages
*Goths or Gothic people, the ethnonym of a group of East Germanic tribes
**Gothic language, an extinct East Germanic language spoken by the Goths
**Crimean Gothic, the Gothic language spoken b ...
elements of the
belfry with the
Romanesque style of the tower. There are seven bells, one for each note of the musical
major scale
The major scale (or Ionian mode) is one of the most commonly used musical scales, especially in Western music. It is one of the diatonic scales. Like many musical scales, it is made up of seven notes: the eighth duplicates the first at double ...
. The largest one was installed in 1655.
History following construction
Between 1589 and 1592,
Galileo Galilei
Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He wa ...
, who lived in Pisa at the time, is said to have
dropped two cannonballs of different
mass
Mass is an intrinsic property of a body. It was traditionally believed to be related to the quantity of matter in a physical body, until the discovery of the atom and particle physics. It was found that different atoms and different eleme ...
es from the tower to demonstrate that their speed of descent was independent of their mass, in keeping with the
law of free fall. The primary source for this is the biography ''Racconto istorico della vita di Galileo Galilei (Historical Account of the Life of Galileo Galilei)'', written by Galileo's pupil and secretary
Vincenzo Viviani
Vincenzo Viviani (April 5, 1622 – September 22, 1703) was an Italian mathematician and scientist. He was a pupil of Torricelli and a disciple of Galileo.[World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposing ...]
, the
Allies suspected that the Germans were using the tower as an observation post. Leon Weckstein, a
U.S. Army
The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cl ...
sergeant sent to confirm the presence of German troops in the tower, was impressed by the beauty of the cathedral and its campanile, and thus refrained from ordering an
artillery
Artillery is a class of heavy military ranged weapons that launch munitions far beyond the range and power of infantry firearms. Early artillery development focused on the ability to breach defensive walls and fortifications during siege ...
strike, sparing it from destruction.
[Shrady, Nicholas (2003): ''Tilt: a skewed history of the Tower of Pisa'']
Numerous efforts have been made to restore the tower to a vertical orientation or at least keep it from falling over. Most of these efforts failed; some worsened the tilt. On 27 February 1964, the government of Italy requested aid in preventing the tower from toppling. It was, however, considered important to retain the current tilt, due to the role that this element played in promoting the tourism industry of Pisa.
Starting in 1993, 870 tonnes of lead
counterweights were added, which straightened the tower slightly.
The tower and the neighbouring
cathedral
A cathedral is a church that contains the '' cathedra'' () of a bishop, thus serving as the central church of a diocese, conference, or episcopate. Churches with the function of "cathedral" are usually specific to those Christian denominatio ...
,
baptistery
In Christian architecture the baptistery or baptistry (Old French ''baptisterie''; Latin ''baptisterium''; Greek , 'bathing-place, baptistery', from , baptízein, 'to baptize') is the separate centrally planned structure surrounding the baptismal ...
, and cemetery are included in the
Piazza del Duomo UNESCO World Heritage Site
A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO). World Heritage Sites are designated by UNESCO for ...
, which was declared in 1987.
The tower was closed to the public on 7 January 1990,
after more than two decades of stabilisation studies and spurred by the abrupt collapse of the
Civic Tower of Pavia in 1989.
The bells were removed to relieve some weight, and cables were cinched around the third level and anchored several hundred meters away. Apartments and houses in the path of a potential fall of the tower were vacated for safety. The selected method for preventing the collapse of the tower was to slightly reduce its tilt to a safer angle by removing of soil from underneath the raised end. The tower's tilt was reduced by , returning to its 1838 position. After a decade of corrective reconstruction and stabilization efforts, the tower was reopened to the public on 15 December 2001, and was declared stable for at least another 300 years.
In total, of soil were removed.
After a phase (1990–2001) of structural strengthening, the tower has been undergoing gradual surface restoration to repair visible damage, mostly corrosion and blackening. These are particularly pronounced due to the tower's age and its exposure to wind and rain.
In May 2008, engineers announced that the tower had been stabilized such that it had stopped moving for the first time in its history. They stated that it would be stable for at least 200 years.
File:Leaning_Tower_of_Pisa_in_the_1890s.jpg, Leaning Tower of Pisa in the 1890s
File:Plaque galileo.jpg, Plaque in memory of Galileo Galilei
Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He wa ...
's experiments
File:Pisa schiefer turm gewichte 1998 01.jpg, Temporary lead counterweights, 1998
File:Pisa Cathedral & Leaning Tower of Pisa.jpg, The Baptistery
In Christian architecture the baptistery or baptistry (Old French ''baptisterie''; Latin ''baptisterium''; Greek , 'bathing-place, baptistery', from , baptízein, 'to baptize') is the separate centrally planned structure surrounding the baptismal ...
(in the foreground), the Cathedral
A cathedral is a church that contains the '' cathedra'' () of a bishop, thus serving as the central church of a diocese, conference, or episcopate. Churches with the function of "cathedral" are usually specific to those Christian denominatio ...
(in the middleground), and the Leaning Tower of Pisa (in the background)
Earthquake survival
At least four strong
earthquake
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, fr ...
s have hit the region since 1280, but the apparently vulnerable tower survived. The reason was not understood until a research group of 16 engineers investigated. The researchers concluded that the tower was able to withstand the tremors because of dynamic
soil-structure interaction (DSSI): the height and stiffness of the tower, together with the softness of the foundation soil, influences the vibrational characteristics of the structure in such a way that the tower does not
resonate
Resonance describes the phenomenon of increased amplitude that occurs when the frequency of an applied periodic force (or a Fourier component of it) is equal or close to a natural frequency of the system on which it acts. When an oscillat ...
with
earthquake ground motion. The same soft soil that caused the leaning and brought the tower to the verge of collapse helped it survive.
Technical information
* Elevation of Piazza del Duomo: about 2 metres (6 feet, DMS)
* Height from the ground floor: ,
8 stories
* Height from the foundation floor:
* Outer diameter of base:
* Inner diameter of base:
* Angle of slant: 3.97 degrees
or from the vertical
[tan(3.97 degrees) * (55.86m + 56.70m)/2 = 3.9m]
* Weight:
* Thickness of walls at the base:
* Total number of bells: 7, tuned to
musical scale
In music theory, a scale is any set of musical notes ordered by fundamental frequency or pitch. A scale ordered by increasing pitch is an ascending scale, and a scale ordered by decreasing pitch is a descending scale.
Often, especially in the ...
, clockwise:
** 1st bell: L'Assunta, cast in 1654 by
Giovanni Pietro Orlandi, weight
** 2nd bell: Il Crocifisso, cast in 1572 by
Vincenzo Possenti, weight
** 3rd bell: San Ranieri, cast in 1719–1721 by
Giovanni Andrea Moreni, weight
** 4th bell: La Terza (1st small one), cast in 1473, weight
** 5th bell: La Pasquereccia or La Giustizia, cast in 1262 by
Lotteringo, weight
** 6th bell: Il Vespruccio (2nd small one), cast in the 14th century and again in 1501 by
Nicola di Jacopo
Nicola may refer to:
People
* Nicola (name), including a list of people with the given name or, less commonly, the surname
**Nicola (artist) or Nicoleta Alexandru, singer who represented Romania at the 2003 Eurovision Song Contest
* Nicola people, ...
, weight
** 7th bell:
Dal Pozzo, cast in 1606 and again in 2004, weight
* Number of steps to the top: 296
About the 5th bell: The name ''Pasquareccia'' comes from ''Easter'', because it used to ring on Easter day. However, this bell is older than the bell-chamber itself, and comes from the tower Vergata in ''Palazzo Pretorio'' in Pisa, where it was called ''La Giustizia'' (The Justice). The bell was tolled to announce executions of criminals and traitors, including
Count Ugolino in 1289.
A new bell was installed in the bell tower at the end of the 18th century to replace the broken ''Pasquareccia''.
The circular shape and great height of the campanile were unusual for their time, and the crowning belfry is stylistically distinct from the rest of the construction. This belfry incorporates a correction for the inclined axis below. The siting of the campanile within the Piazza del Duomo diverges from the axial alignment of the cathedral and baptistery of the Piazza del Duomo.
''Guinness World Records''
Two German churches have challenged the tower's status as the world's most lopsided building: the 15th-century square
Leaning Tower of Suurhusen
The Leaning Tower of Suurhusen (german: Schiefer Turm von Suurhusen) is a late medieval steeple in Suurhusen, a village in the East Frisian region of northwestern Germany. According to the Guinness World Records it was at one time the most tilte ...
and the 14th-century bell tower in the town of
Bad Frankenhausen
Bad Frankenhausen (officially: Bad Frankenhausen/Kyffhäuser) is a spa town in the German state of Thuringia. It is located at the southern slope of the Kyffhäuser mountain range, on an artificial arm of the Wipper river, a tributary of the Uns ...
. ''
Guinness World Records
''Guinness World Records'', known from its inception in 1955 until 1999 as ''The Guinness Book of Records'' and in previous United States editions as ''The Guinness Book of World Records'', is a reference book published annually, listing world ...
'' measured the Pisa and Suurhusen towers, finding the former's tilt to be 3.97 degrees.
In June 2010, ''Guinness World Records'' certified the
Capital Gate
Capital Gate, also known as the Leaning Tower of Abu Dhabi, is a skyscraper in Abu Dhabi that is over tall, 35 stories high, with over of usable office space. Capital Gate is one of the tallest buildings in the city and was designed to incline 1 ...
building in
Abu Dhabi,
UAE
The United Arab Emirates (UAE; ar, اَلْإِمَارَات الْعَرَبِيَة الْمُتَحِدَة ), or simply the Emirates ( ar, الِْإمَارَات ), is a country in Western Asia (The Middle East). It is located at th ...
as the "World's Furthest Leaning Man-made Tower";
it has an 18-degree slope, almost five times more than the Tower of Pisa, but was deliberately engineered to slant. The
Leaning Tower of Wanaka in
New Zealand
New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...
, also deliberately built, leans at 53 degrees to the ground.
'Leaning and tumbling towers'
on Puzzling World website, viewed 30 July 2011
Gallery
File:Lightmatter pisa.jpg, View looking up
File:Leaning tower door.JPG, Entrance door to the bell tower
File:Leaning tower loggiati.jpg, External loggia
In architecture, a loggia ( , usually , ) is a covered exterior gallery or corridor, usually on an upper level, but sometimes on the ground level of a building. The outer wall is open to the elements, usually supported by a series of columns ...
File:Leaning tower staircase 6th floor.jpg, Inner staircase from sixth to seventh floor
File:Leaning tower staircase 7th floor.JPG, Inner staircase from seventh to eighth (the top) floor
File:Leaning tower staircase 8th floor.JPG, View from the top
File:View, looking down from top of Leaning Tower of Pisa.jpg, View, looking down from the top
File:The Leaning Tower of Pisa SB.jpeg, Leaning Tower of Pisa in 2013
File:Tower of Pisa - push.jpg, Tourist in a common pose at Tower of Pisa, June 2009
See also
* Leaning Temple of Huma
The Leaning Temple of Huma in India is one of only two leaning temples in the world. It is located in Huma, a village situated on the bank of the Mahanadi River, Mahanadi, 23 km south of Sambalpur in the Indian state of Odisha, India, Odi ...
* List of leaning towers
This is a list of leaning towers. A leaning tower is a tower which, either intentionally or unintentionally (due to errors in design, construction, or subsequent external influence such as unstable ground), does not stand perpendicular to the gr ...
** Leaning Tower of Niles
The Leaning Tower of Niles is a half-size replica of the Leaning Tower of Pisa. Located in Niles, Illinois, it was completed in 1934 by industrialist Robert Ilg as part of a recreation park for employees of the Ilg Hot Air Electric Ventilating ...
, a replica of the Tower of Pisa
** Leaning Tower of Zaragoza, was a famous European leaning tower
** Great Mosque of al-Nuri (Mosul)
, native_name_lang = ara
, image = Ancient Mosul, a Yezidi shrine to the left and the Nouri Mosque minaret to the right.jpg
, image_upright = 1.4
, alt =
, caption = Al Nouri mo ...
, an ancient leaning tower that stood until 2017; reconstruction efforts are currently underway
* Round tower (disambiguation), for other types of round towers
* The Greyfriars Tower, the remains of a Franciscan monastery in King's Lynn, nicknamed "The Leaning Tower of Lynn"
* Torre delle Milizie
The Torre delle Milizie ("Tower of the Militia") is a fortified tower in Rome, Italy, located between Trajan's Market in the Imperial fora to the southwest and the Pontifical University of Saint Thomas Aquinas, or Angelicum, to the east.
Histor ...
, a tilting medieval tower in Rome
* Tour de Pise, a rock dome in Antarctica, was named after this tower
References
External links
* official site
Piazza dei Miracoli digital media archive
( Creative Commonslicensed photos, laser scans, panoramas), data from a University of Ferrara
The University of Ferrara ( it, Università degli Studi di Ferrara) is the main university of the city of Ferrara in the Emilia-Romagna region of northern Italy. In the years prior to the First World War the University of Ferrara, with more than 5 ...
/CyArk
CyArk (from "cyber archive") is a 501(c)(3) nonprofit organization located in Oakland, California, United States founded in 2003. CyArk's mission is to "digitally record, archive and share the world's most significant cultural heritage and ensure ...
research partnership, includes 3D scan data from the Leaning Tower of Pisa.
*
{{Authority control
1372 establishments in Europe
Bell towers in Italy
Buildings and structures completed in 1372
Inclined towers
Round towers
Romanesque architecture in Pisa
Tourist attractions in Pisa
Towers completed in the 14th century
Towers in Pisa
World Heritage Sites in Italy
Christian bell towers