Domine Quo Vadis
A church situated on the Appian Way near Rome, on the traditional spot where, according to Saint Ambrose, Saint Peter was vouchsafed a vision of Christ.
At the urgent request of the Christians, Peter was fleeing the persecution of Nero, when, seeing Christ, he fell at His feet crying "Lord, whither goest Thou?"
Christ's reply that He was going to Rome to be crucified anew was interpreted by Peter as a sign to return to Rome, and he therefore retraced his steps to the city.
New Catholic Dictionary