While many of Italy's cathedrals are referred to as "Il Duomo," coming from the Latin word for "House," only Florence's can claim the title of the biggest masonry dome in the world. It is easy to see why a work of this magnitude energized Florence's populace and helped usher in the Renaissance. The church had been unfinished for almost 125 years, when the first stone was set in 1296. Master architect and Renaissance Florentine Filippo Brunelleschi's brilliant design finally capped off this massive cathedral. While the multicolored marble facade dates from only about the mid-19th century, the dome has stood the test of time, dominating Florence's skyline for over 500 years. The best way to get a sense of this achievement is to strap on some good shoes and hike up the 463 steps yourself.