Immediately to the south of the fortress was the principal market-place of the town, surrounded by porticoes on its four sides, and hence named the Tetrastoon.
The streets, never very wide, became narrower, and the porticoes along their sides were almost everywhere removed.
The site was excavated in 1894, and traces of a sacred agora with porticoes and other buildings, as well as the temple, have been found.
From this side the sacred precinct of Apollo is approached by an avenue flanked by porticoes, that upon the seaside bearing the name of Philip V.
At the north of the precinct was a broad road, flanked with votive offerings and exedrae, and along the boundary were porticoes and chambers intended for the reception of the OEwpiac or sacred embassies; there are two entrances on this side, each of them through extensive propylaea.