Leaning Tower of Pisa Facts
The height, the history, and the reason it leans — everything worth knowing before you climb.
Why Does the Leaning Tower of Pisa Lean?
The Tower began tilting during construction in the 12th century. Its foundation is only about three meters deep, set into soft, unstable subsoil that couldn't evenly support the structure's weight — so one side began sinking before the tower was even finished.
A 199-Year Construction
Construction started in 1173 and wasn't completed until 1372 — 199 years later, across three separate building phases. Work was interrupted twice by nearly a century of wars, which architectural historians now believe accidentally let the soil beneath the tower settle, saving it from toppling early on. The identity of the original architect is still debated, though Bonanno Pisano is traditionally credited, with later phases led by Giovanni di Simone and Tommaso Pisano.
The 1990s Stabilization Project
By the 20th century the lean had become dangerous. Between 1993 and 2001, engineers removed roughly 70 metric tons of soil from beneath the raised side and added 870 tonnes of lead counterweights, reducing the tilt by 45 centimeters back to its 1838 position. The Tower was closed to visitors throughout the project and reopened in 2001, declared stable for at least another 300 years.
Climbing to the Top
Today's visitors climb a spiral staircase of 296 steps through the Tower's 8 stories to the bell chamber at the top, where the lean is most noticeable underfoot — and where the view stretches across Piazza dei Miracoli and the Tuscan countryside beyond.
