The Leaning Tower of Pisa is the bell tower of the cathedral in Pisa, Italy. It is tilted at an angle of 4 degrees due to unstable soil. Construction began in 1173 but was halted multiple times due to wars and structural issues as the tower began to sink. It took over 200 years to complete the tower which is 58 meters tall and weighs 14,453 tonnes. Today visitors can tour the tower but access is restricted and advance tickets are required.