- St. Peter's Basilica: Its roots began with the first Christian emperor, Constantine, in A.D. 324. By 1400, the Roman basilica was in danger of collapsing, prompting the Renaissance popes to commission plans for the largest, most impressive, most jaw-dropping cathedral the world had ever seen. Amid the rich decor of gilt, marble, and mosaics are countless artworks, including Michelangelo's Pietà. Other sights here are a small museum of Vatican treasures and the eerie underground grottoes containing the tombs of former popes, including the most recently interred, John Paul II. An elevator ride (or a rigorous climb) up the tower to Michelangelo's glorious dome provides panoramic views of Rome.
- Pantheon: Architects have called the Pantheon "the world's only architecturally perfect building." The best preserved ancient Roman structure was built by Hadrian in A.D. 119–128 as an ancient temple (later a church). The immense dome, still intact, would remain as the largest ever built for centuries to come.
- Basilica di Santa Maria Maggiore: One of Rome's oldest and most striking cathedrals, this church dates from the 5th century. In the 14th century, the city's tallest bell tower was added. Later in the 18th century a new facade was added. Legend has it that it was gilded with the first gold to arrive from the New World.
- Basilica di San Giovanni in Laterano: The oldest Christian church within the city walls, this landmark was for years the seat of the papacy and the heart of Christianity, a role played by St. Peter's today, of course. The Emperor Constantine donated the land to the newly sanctioned sect of Christians in A.D. 314. In 1646 Borromini rescued the church from decay, creating a baroque basilica but with elements of the ancient structure kept intact.
- Santa Maria d'Aracoeli: Visits here are tied in with trips to the adjoining Piazza del Campidoglio. First mentioned in the 7th century, the church today dates mainly from A.D. 1250 when it came under the Franciscans. The Tiburtine Sibyl was said to have told the Emperor Augustus to build an "altar to the first among gods," and he dutifully constructed this aracoeli (Altar in the Sky). The first chapel on the right was frescoed by Pinturicchio, the Umbrian Renaissance master.
- St. Paul Outside the Walls: One of Rome's four grand pilgrimage basilicas, San Paolo Fuori le Mura was destroyed by fire in 1823 but reconstructed. The church is believed to have been erected over the tomb of St. Paul. The stunning windows appear to be stained glass but are actually made of translucent alabaster.
- Santa Maria Sopra Minerva: Built over a former Temple of Minerva, Santa Maria is Rome's only Gothic church, dating from 1280. Before entering, look for the whimsical statue by Bernini of a baby elephant on the square out front. The last chapel in the church is filled with many treasures, notably a delicious cycle of frescoes by Filippino Lippi (last chapel on the right).
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.