Pisa's main claim to fame is the leaning tower. Not that it was designed that way, but... Construction began in 1173, but was suspended after 10 years and at 3 stories due to the lean which was already visible! Another architect resumed building in 1275, but with a "kink" (still visible) to compensate for the lean. Construction stopped for a second time at 7 stories in 1284 due to excessive lean. The third building construction occured in the mid 1300s when the belfry was added, bringing the total height to 54 metres. Work is now underway to very slowly reduce the angle of lean, as it was threatening to tip over. The technique adopted is to very slowly remove soil from below the high side; the weight of the tower then equalises the soil and slowly the tower has been coming back to more vertical. The goal is to have as much lean as possible while ensuring the tower will not fall over. And the lean also puts extra load on the structure, which has been investigated only to discover that it has many voids, and so is not as strong as it might appear from the apparently solid exterior!
The tower was closed to the public 1990, and only re-opened in 2001, after the lean had been reduced. The lean is now about 5 degrees, which results in the top being about 3 metres further south than the base! Which is, of course, why Galileo used it when determining that the rate of fall of objects is the same for all objects (independent of mass; wind resistance being ignored).
What lean? Looks pretty vertical to me. However, if it falls, and you happened to be standing here, you'd pretty quickly become two dimensional!
This photo was taken from an angle approximately 90 degrees around the tower from the one above. The lean is pretty amazing!
This photo also shows the lean by comparison with the pedestal in the foreground. And the bend at the top (the belfry) is quite visible. It was probably vertical when the tower was finished! Could this be called "jerry building"?
Visitors are now allowed onto the tower, but in small numbers, and bookings are essential (according to what I was told). This photo also shows the lean by comparison with the side of the cathedral (the building on the left).
The Entrance
Enjoying Some Shade
The left image shows the entrance (with the obligatory guard), and also how low the low side has become, as the base on this side is close to ground level (visible on the tower's right in the right hand photo), and the ground itself is flat and level!
Ah, the Municipal Police - ready for hot pursuit on their motor scooters! And they're so pretty.
The view from the bus on the way back to Florence. And another hill, with towers! Two of them. I think the one on the right is church steeple, though it's rather difficult to tell in the photo.
And so we had a very uneventful return journey. I walked back to the hotel to drop off the tourist equipment and head out for another fine meal. And planned on a quiet night, for tomorrow was into the hills around Florence on the Chianti tour!
Pisa Cathedral
Italy In July