Amphipolis, an ancient Greek city on the Strimon River just inland from the north shore of the Aegean Sea. It was founded by Athenians in the mid-fifth century B.C. to serve as a military outpost, a trade center, and a base for mining gold from the nearby Pangaion Mountains. During the Peloponnesian War (431-404 B.C.) Amphipolis was captured by Sparta, and then was made autonomous. In 357 B.C. Philip of Macedon seized the city to gain control of the coast and of the gold mines. After a few centuries the gold gave out and Amphipolis sank into obscurity.