Rome is a city of magnificent art. It's everywhere you look, and most of it was paid for by the Church. Public squares like Piazza Navona — with Bernini's much-loved Four Rivers fountain — are decorated with Church-sponsored art.

Until modern times, it was the Church that had the power, the money, and the need for great art. And going to church offered the masses — whose lives were so dreary otherwise — a promising glimpse of the glory that awaited them in the next life.

And, visiting today, our challenge is to appreciate the art from that perspective — as a medieval worshipper. Popping into churches — many of them nondescript on the outside — you'll find sumptuous art treasures inside. The wonderful thing about seeing art in churches is that it's in situ — not hanging on museum walls, but exactly where the art was designed to be enjoyed. Thoughtfully stringing together a series of lesser-known churches can be an art lover's delight.

For example, dropping by the relatively obscure Santa Maria sopra Minerva we find a glorious Gothic interior laden with impressive art. The altar sits upon the tomb of St. Catherine, with the ornate tombs of two Medici popes looking down. For generations, pilgrims have marveled at this Michelangelo statue of Christ carrying the Cross. And, in the side chapel, is a lovely series of frescoes by Filippo Lippi showing the good works of St. Thomas Aquinas accompanied by a celestial serenade.

Another even less-visited church, Santa Prassede, is decorated with the best Byzantine mosaics in Rome. They date from the 800s.

In this chapel, the gold ceiling represents heaven. An icon-like Christ emerges from the background, supported by winged angels in white. Saints walk among patches of flowers, while Mary and Jesus overlook the altar. While this small chapel is impressive even to our modern eyes, in the darkness of medieval Rome it was stunning — celebrated as the "Garden of Paradise."

Another gem awaiting those exploring Rome's back streets is the Church of St. Peter-in-Chains. Its fine side altar was sculpted during the Renaissance, an age when realism, emotion, even psychology were injected into the art. Its centerpiece is a masterpiece by Michelangelo.

Michelangelo tells a story in marble: Moses has just returned from a meeting with God. He senses trouble back home. He turns to see his followers worshipping a golden calf. Gripping the Ten Commandments under his muscular arm, he's about to rise up and punish the naughty Children of Israel.