The Leaning Tower of Pisa Reopens After Engineers Make It Straighter — But Not Straight

Please fix the tower. Do not fix the tower.

The Leaning Tower of Pisa had been leaning for centuries.

That was the attraction.

It was also becoming a structural problem.

By the late twentieth century, engineers were sufficiently concerned about its stability that the tower was closed to visitors in 1990.

Then began one of conservation engineering's stranger assignments:

Stop a famous leaning building from falling over without stopping it from being famously leaning.

Straightening the tower completely would have solved the wrong problem.

Its inclination was not merely a defect.

It was the monument's identity.

The international engineering committee therefore sought a solution that would improve stability while preserving the tower's historic character.

Intervention had to be kept minimally invasive and visually unobtrusive.

After years of studies, counterweights, temporary safeguards and monitoring, engineers used a technique known as soil extraction or underexcavation.

Small amounts of soil were carefully removed from beneath the higher side of the foundation.

The tower responded gradually.

Its lean decreased.

Not dramatically.

That was the point.

Engineering accounts describe the reduction as deliberately small enough that the casual observer would scarcely notice it.

Contemporary reporting put the correction at roughly 44 centimetres, returning the tower approximately to the inclination it had possessed in the nineteenth century.

After more than a decade closed to ordinary visitors, the tower officially reopened on Saturday, 15 December 2001.

Visitors could climb it again.

It was safer.

It was more stable.

And, crucially for tourism, it was still visibly wrong.

Few restoration projects can be summarized quite this way:

Experts spent years making a building straighter while ensuring that nobody would mistake it for straight.