11 And having set sail from Troas, we ran a straight course to Samothrace, and on the next day to Neapolis 12 and from there to Philippi, which is a prominent city of the District of Macedonia, a colony, and we stayed in this city some days. Acts 16:11-12 (translated from the from the NA28 Greek text)
As you know, Paul’s friend and companion Luke wrote the book of Acts in the New Testament. In Acts 16:10, we read that after Paul had seen the vision to leave Asia and come to Europe after seeking the will of God for the next focus of his missionary journey, Luke includes himself in the narrative as an eyewitness, therefore, his account of what happened to Paul and Silas in Philippi are given as one who was there.