This is possibly the most interesting tourist attraction of the city: it's a bell tower 112 metres…read morehigh, making it one of the highest in the world, and the highest red brick-built. It has been decorated with the biggest astronomical clock in the world, showing, along with date and time, lunar phases and zodiac signs.
Getting to the top can be challenging, as there is no lift (not surprising considering that this building is nearly one thousand years old), but the views all the way up are superb, and get better as you appraoch the top.
One should chose windier days, to enjoy the best views, and this can be problematic: the Po plain is enclosed by mountains, and wind is rare. The air is often very foggy, particularly in winter, or misty enough for people not to take the most of the views.
When the alps are visible in the far distance from the roads around the town, one shouldn't miss the occasion to walk up the Torrazzo: they can be sure they won't be disappointed. The whole city can be seen, along with huge portions of the countryside and parts of the river.
The price is usually around 5€ but it might vary, though not so much, as the building is managed by the Diocese who might decide that they need more money any time.