It's only when you see the leaning tower of Pisa close up that you realise what all the fuss is about. For the tower is undoubtedly elegant and beautiful - a wedding cake confection in glistening white and pink marble, with eight circular tiers of columns stacked one on top of the other, and rising 58 metres above the Tuscan plain, writes Mary Mulvihill.
But its architectural beauty is not the first thing you notice. No, the first thing that strikes you is that the leaning tower of Pisa is not leaning at all. It is, in fact, falling. . .engaged in a head-on battle against gravity, a battle that will end, sooner or later, in tears and broken masonry. Of course, the engineering and technical team that just spent $25 million and 12 years attempting to stabilise the tower, so that it is once again open to visitors, hopes it has postponed this fatal day for at least 200 years.
Yet just one look at this falling bell tower will have you wondering. The structure has a pronounced kink - as if the top five storeys had broken off and been awkwardly glued back on - and the final storey, which houses the bells, currently overhangs the ground floor by a vertigo-inducing 4.5 metres.
Technical investigations
No surprise then, that computer simulations predict the tower should already have fallen, and that in 1990 it was deemed unsafe and closed to the public, pending technical investigations aimed at halting, if not undoing, some of the tilt.
The tower, begun in 1173, is part of a beautiful ecclesiastical compound that also includes Pisa's cathedral and baptistery. All three structures were built on the same soft sediment from an ancient river bed, but only the tower has subsided, probably because its 14,500 tonnes are concentrated on a narrow base measuring just 20 metres across.
Even as the first three floors were finished, they began to tilt ominously. Picture a tense meeting at the site, as builder, architect and clergy gather to inspect the now non-vertical edifice. Should they demolish it? Straighten it? Let gravity take its course? Or give full rein to their artistic Italian nature, and create something new and unique?
Why, in years to come people from all over the world might pay good money to climb it!
When the next three floors were eventually added a century later, they were made slightly higher on the tower's down side. This compensated somewhat for the tilt, but gave the tower a distinctive crooked, almost banana-like shape.
The final storey was added another century later, a full 200 years after the foundation stone was laid, and after several delays occasioned not just by the subsidence, but also adjournments for wars with neighbouring Florence and Genoa.
Since then, the tower has been toppling over gently at a rate of about one millimetre a year, and by 1838 the southern side had sunk a total of nearly three metres.
Millennium Tower
Contrast that with Glasgow's new Millennium Tower: this was closed to the public in March when the authorities discovered it had sunk a mere 100 millimetres. A major programme is now under way to jack it up. But if Pisa is anything to go by, the good burghers of Glasgow have made a mistake: it is not the tower they should be jacking up, but the admission prices.
For now that Pisa's tower is again open to the public, there is no shortage of people willing to queue up and pay €15 for the privilege of climbing 294 steps up the dizzying inner spiral staircase to the top (no elevators, no disabled access, and you are thrown first one way, then the other, as you wind your way up the tilting steps.
To protect the tower - or maybe help to stave off the day when the whole thing comes toppling down - tours are limited to 30 people and last just 25 minutes. Happily, that still leaves plenty of time to enjoy the view from the top (snow-capped Apennine peaks, rolling Tuscan plains and pretty terracotta roofs).
There have, of course, been plenty of attempts over the centuries to save the tower. And plenty of wild suggestions too - such as tying helium balloons to it, and removing the upper storeys. There are those who fear that any intervention could exacerbate the tilt, and others who believe the tower should be left to the mercy of gravity.
And at Pisa they know all about gravity. Galileo Galilei was born there, the man who reputedly dropped cannonballs from the top of the tower to prove a point about gravity - demonstrating in the process what will happen to the tower when that inexorable force eventually has its way.
Latest operation
The latest international rescue operation proceeded with extreme caution, taking years to decide on an approach - bearing in mind that any intervention must be reversible - and as many years again to do the work. First, the experts added 600 tonnes of lead weight to the tower's higher side. Next, they attached steel cables to hold the tower in place.
Finally, they removed soil from under the tower's high side, using corkscrew drills, in an attempt to level the pitch. They also installed sophisticated monitoring equipment so that, if and when the tower does start to fall, there should be plenty of advance warning.
By June last year, they had successfully turned back the clock, and returned the tower to its 1838 position. And in December, on a sunny but bitterly cold Saturday, the tower reopened, and the bells rang out.
Yours truly was fortunate enough recently to be able to buy a ticket for the final tour of the day, and enjoy a glorious sunset from the top. Anyone wanting to do likewise at this time of the year, however, would be well advised to book their ticket in advance.