Apostle Paul is an amazing person who influenced Christianity more than anyone else, after Jesus Christ. He taught the gospel of Jesus Christ to the 1 Century world. Approximately half of the book of Acts deals with Paul's life and works. But he was not one of the 12 apostles.
The New Testament outlines at least fifty cities visited during his major missionary journeys. From the mid-30s to the mid-50s AD he founded several Christian communities in Asia Minor and Europe.