Baptistry Ceiling, Florence

While the bronze doors of Florence's Baptistry get the attention from art historians, it's the mosaics inside that wow most visitors. Step into the cool dimness and look up. A gigantic Jesus passes judgement, while stories from the Old and New Testaments play out in rows. Starting in the 13th century, a hundred years' worth of lifetimes passed while unknown numbers of craftsmen worked on the ground and then up inside the dome to create this glittering masterpiece. In our present-day world of color and distraction it's rare to find something truly glorious and awe inspiring.  This still holds all of its power and glory.