The Leaning Tower of Pisa is one of the most famous structures in the world. Located in the Italian city of Pisa, the tower is instantly recognizable because of its dramatic tilt. Although many people know about its unusual lean, fewer know the long and complex story of when and how it was built. The Tower of Pisa was not constructed in a single year or even in a single generation. Instead, its building stretched over nearly two centuries, from the 12th to the 14th century. This long timeline, shaped by wars, political struggles, and engineering challenges, is a major part of the tower’s history.
The Beginning of Construction (1173)
The construction of the Tower of Pisa began in August 1173. At that time, Pisa was a powerful maritime republic, rich from trade across the Mediterranean Sea. The city wanted to show its wealth, faith, and power through impressive religious buildings. The tower was designed as the bell tower (campanile) for the nearby cathedral in the Piazza dei Miracoli, also known as the Square of Miracles.
Although the exact architect is still debated, many historians believe the original design was created by Bonanno Pisano, a sculptor and architect, or possibly Guglielmo di Innsbruck. The plan was for a tall, straight, and elegant Romanesque-style tower built from white marble.
Early Construction and the First Lean (1173–1178)
The first stage of construction lasted about five years. During this time, the builders completed the foundation and the first three floors. The foundation, however, was only about three meters deep and was built on soft soil made of clay, sand, and shells.
By 1178, the workers noticed that the tower had started to lean. The ground beneath one side of the foundation was sinking more than the other, causing the structure to tilt. Alarmed by this unexpected problem, construction was stopped.
The Long Pause (1178–1272)
For nearly 100 years, no work was done on the tower. This pause was partly due to the leaning problem, but also because Pisa was involved in wars with neighboring cities such as Genoa, Lucca, and Florence.
Ironically, this long delay helped save the tower. The soil beneath the foundation had time to settle and compact, which prevented the building from collapsing.
Second Phase of Construction (1272–1284)
Work resumed in 1272 under a new architect, Giovanni di Simone. He attempted to correct the lean by making the upper floors slightly taller on the sinking side. This created the tower’s famous curved shape.
During this phase, the builders added three more floors. However, construction was again halted in 1284 after Pisa suffered a major naval defeat by Genoa.
Final Completion (1372)
The tower remained unfinished for nearly a century until work resumed once more in 1360. The final stage was completed in 1372 under the architect Tommaso di Andrea Pisano, who added the bell chamber at the top.
At completion, the tower stood about 56 meters (183 feet) tall on its higher side and slightly shorter on the lower side.
Why It Took 199 Years
From start to finish, the Tower of Pisa took 199 years to complete. The long construction period was caused by:
- Unstable soil and structural problems
- Wars and political conflicts
- Financial difficulties
- Attempts to correct the lean
A Living Monument
Today, the Leaning Tower of Pisa stands as a symbol of patience, resilience, and human creativity. Its long construction history shows how challenges can shape great achievements.