dr.schliemann: I remember that at the end of 80s many people were worried for the tower's destiny.
Its inclination was so high that the tower was closed and it was a shame because FIFA World Cup 1990 was held in Italy and many tourists couldn't climb the tower. Then heavy restoration's works started and they lasted until 2001, when the tower has been finally opened again. It's a shame to see
those lead counterweights, but it's the only solution because the soil is mostly made of sand and that's why the tower tends to lean. Anyway during the last years the tower has been also restored aesthetically.
I got lucky and had a chance to climb the tower as a kid (88 or 89, can't remember), nowadays as a grownup I would no longer do that because the preservation of this irreplaceable national treasure is more important than satisfying a personal touristy need. Must admit though that climbing up the spiral stairs at the time when the tower was at its most "leany" point in history was quite a memorable experience. I remember exactly how weird it felt and how I almost got dizzy.
According to engineers, the tower is now stable for however long they say but I'm not so optimistic, I'll definitely not climb the tower again because every visitor that goes up there decreases the amount of time until the next restoration is required by a tiny bit.