PIAZZA DEL DUOMO, Italy — Moving the Leaning Tower of Pisa an inch and a half back in November 2018 has likely given it centuries more stability.

The famous bell tower, built with an unintentional slant in the 12th century, was re-slanted in the months before the new year and is standing more upright. It tilted the inch-and-a-half in the last 17 years.

It's a small number that has big impact.

When the work began, the tower was leaning 13 feet off the perpendicular south side, CNN reports. Soil was removed on the opposite side to reverse its trajectory.

It probably has been given two more centuries worth of stability from that tiny move, but the reduction of the slant will not last forever, said Professor Salvatore Settis .

The Leaning Tower of Pisa gets thousands of tourists visiting it per day.