21 June. Paul leaves Aquila and Pricilla in Ephesus
"Paul stayed with the believers [in Corinth] for many more days. Then he left and sailed for Syria, with Priscilla and Aquila. At Cenchrea [the southern port of Corinth] Paul cut off his hair, because he had made a promise to God."
"Then they went to Ephesus, where Paul left Priscilla and Aquila. While Paul was there, he went into the synagogue and talked with the Jews. When they asked him to stay with them longer, he refused. But as he left, he said, 'I will come back to you again if God wants me to.' And so he sailed away from Ephesus."
"When Paul landed at Caesarea, he went and gave greeting to the church in Jerusalem. After that, Paul went to Antioch [his home church, in Syria]. He stayed there for a while and then left and went through the regions of Galatia and Phrygia. He travelled from town to town in these regions, giving strength to all the followers."
(Acts 18:18-23)
After spending eighteen months in Corinth, Paul left with his friends Aquila and Priscilla and sailed from Cenchraea (the Aegian port of Corinth) to Ephesus (see 6 on the map).
Paul preached in the synagogue at Ephesus and was encouraged to stay longer. But he wanted to get back to Jerusalem before the end of the sailing season (the beginning of November), so he left Aquila and Pricilla in Ephesus, promised to return at a later date, and set sail for Caesarea (see 7 on the map).
After landing at Caesarea in October or November 52AD, Paul went up to Jerusalem to report back to the church leaders (see 8 on the map); then he returned to his ‘home’ church at Antioch in Syria (see 9 on the map).
After several months in Antioch, Paul set out again with Timothy on his "third missionary journey" in 53AD, and revisited the believers in Galatia and Phrygia in the local churches they'd established there three years earlier in 50AD.
The map shows Paul's 'Second Missionary Journey' which lasted from 50AD to 52AD.
You can read about the whole of this missionary journey starting at https://www.thebiblejourney.org/…/paul-starts-his-2nd-miss…/