Athens is down the coast from Barea which is in Macedonia. Athens was one of the most important cities in Greece. (See: [[rc://en/ta/man/translate/translate-names]])
This speaks about their agitating people as though it were a person stirring a liquid and causing the things at the bottom of the liquid to rise to the surface. Alternate translation: "went there and agitated" or "went there and disturbed" (See: [[rc://en/ta/man/translate/figs-metaphor]])