PISA TOWER

A UNESCO World Heritage Site and one of the most recognized buildings in the world, the Leaning Tower of Pisa ("torre pendente di Pisa," in Italian) in Italy's Tuscany region famously tilts to the southwest, a condition created when its original architects set its foundation in loose, shifting earth. Efforts to correct the tower's posture during its 800-year history have resulted in a reduction in its tilt, and a recent overhaul completed in 2001 added a level of stability this medieval tower never had.
Location
The tower is part of Pisa's Piazza del Duomo (Cathedral Square), a plaza dominated by Pisa's Duomo (cathedral), its Baptistery and Campo Santo (walled cemetery), all built in the medieval Romanesque style. The tower is the cathedral's campanile, a free-standing bell tower. Pisa sits near the Mediterranean coast in Tuscany, about 50 miles east of Florence.
Construction History
Construction on the campanile began on Aug. 9, 1173, on the site of a dry estuary with sandy, unstable soil. During the next five years, workers built three stories of the tower, then abruptly stopped construction. Building resumed in 1272 and continued for five years, at which time the seventh story leaned about 1 degree off center (equivalent to 2.7 feet). Workers completed the tower, with chambers for seven colossal bells, in 1370. Various excavations and the addition of the bells causes the tower to lean more than 13.5 feet by the early 20th century.
Architecture
Workers used gray marble, limestone and stones to build the tower. Its Romanesque style employs a colonnaded facade with Corinthian capitals topping the columns. Inside, 294 steps or 296 steps lead to the tower's top: workers built two fewer steps on the seventh story to compensate for its shorter height on the southwest side.
Inclination
Before the most recent effort to save the tower from collapse, its inclination was about 5.5 degrees, or almost 15 feet off its axis. Extensive restoration projects between 1990 and 2001 gradually reduced the tilt by inches and, more importantly, stabilized the foundation with a complex system of lead weights.
Visiting the Tower
Tourists may go inside the Leaning Tower of Pisa under strict regulations. Timed tickets let in only 40 people at a time for a 30-minute guided tour, which involves climbing the nearly 300 steps to the summit for views of the entire city. Advanced reservations guarantee admission to this popular
landmark