Where did the apostle Paul preach his first sermon?

The Apostle Paul wrote of meeting Peter in Jerusalem, where he seemed to have been a pillar of the church and an assistant to James. Peter also went to Syria. It seems unlikely that Peter would have departed far from Jerusalem, at least until the events of 66-70 CE, by which time he would have been an old man.

A later Christian tradition is that Peter went to Rome to lead the church there. However, Acts of the Apostles, written around the end of the century, does not mention this. Clement of Rome, who should have known if Peter had been in Rome, wrote briefly (1 Clement) of the life of Peter but does not mention his presence in Rome.