Also at Porta San Sebastiano stands the largest and best preserved of the fortified gates in the Aurelian Wall that embraced the seven hills of Rome for more than a thousand years. The twin gate towers house a small museum of wall artifacts. Here you can walk along the top of the wall for postcard views of the Appian Way and the distant Alban Hills. All about are vineyards producing Rome's refreshing Frascati wine.

Beyond the narrow ancient gate, the road dips slightly into a valley covering a maze of catacombs where thousands of bodies were buried along five levels of tunnels. Rome has more than 60 catacombs, some not yet fully explored.

The two most important catacombs open to the public along the Appian Way are St. Sebastian and St. Callixtus, where most of the early popes and many martyrs were buried. Walls and ceilings have paintings and frescoes of early Christian symbols like the fish, the dove and the anchor, and scenes from Scripture such as Jonah swallowed by the whale, Daniel in the lions' den, the raising of Lazarus and, most often, the Good Shepherd.

Over the centuries, pilgrims scratched graffiti invocations to Peter and Paul on the walls of the catacombs of San Sebastian. Here the two apostles were united in death when their bodies were reburied together for a time during the persecutions of the Emperor Valerian.

Nearby, down a side road called Vigna Randanini, are Jewish catacombs, excavated in the third century. The chambers have Latin and Greek inscriptions and the recurring symbol of the seven-branch candlestick. They are rarely open, and then only to guided groups.

A year ago, archaeologists exploring the Catacombs of St. Peter and Marcellinus uncovered a chamber with more than 1,000 skeletons arrayed in elegant togas, some interwoven with gold thread. Tests are under way to determine whether the neatly piled remains were victims of mass executions or a deadly plague late in the first century.

The catacombs were dug by crews of "fossores" — gravediggers — who by the dim light of oil lamps tunneled out the labyrinthine galleries, carrying away the earth in baskets and using "lucemaria" — skylights or air shafts — for ventilation. In these subterranean passages, the early Christians hid out and held services during times of severe persecution. A millennium later, when the great gothic cathedrals were rising across Europe, grave robbers plundered the underground tombs for relics.

Rome's oldest golf course, the Circolo del Golf di Roma, is found here too, where senators, diplomats and movie moguls tee off along lush fairways framed by the arches of the Claudian aqueduct.

It was also along the Appian Way that Paul of Tarsus, a prisoner in chains, who had come to plead with the Emperor Nero for his life, had his first view of Rome, the gilded temples and palaces shimmering in the distance.