Description The third largest cathedral in the world, simply called 'the Duomo', this imposing structure of marble is one of the most flamboyant and grand piece of Gothic architecture in Italy. On the terrace, numerous turrets, spires, pinnacles, and statues weave a lacy extravaganza of marble. Though the climb of 919 steps to the terrace may leave one winded, its well worth the climb to experience such a unique sight at the top.