The territory of New Halos occcupied the Sourpi plain and a large part of Othris mountain, covering an area of c. 500 km2. The city shared the area of the Krokian plain, nowadays Almiros plain, with Phthiotic Thebai, a city on the opposite side of this plain. Archaeological surveys have been conducted in the territory of New Halos and showed that the occupation was concentrated on the plains and in the foothills of Othris mountain. It is likely that in Hellenistic times as nowadays the pastures of Othris mountain were used by transhumant pastoralists. The results of the surveys will be presented separately.

An inscription of the 2nd century BC refers to a degree between the cities of Halos and Phthiotic Thebai. It might be wondered whether Halos survived as a polis although the town of that name physically was destroyed by the earthquake of 265 BC. The cities quarreled about ‘sacred lands’ claimed by both parties. They brought the border dispute for decision by Makon of Larisa as arbitrator. The decree had to be placed in the sanctuary of Artemis Panachaia in Halos and also in sanctuaries at Delphi, Larisa and Thebai. This decree possibly also points to the existence of a sanctuary at the border between Thebai and Halos which was not allocated to either party.