A programme, combining a physical survey, intensive pick-up and geophysics, was carried out over 17 ha around the site of a small late Roman fortification, some 6 km south of ancient Pydna. Although the area is intensively farmed, the pick-up survey proved remarkably successful. Hellenistic occupation was identified and a restricted Roman settlement around the site of the quadriburgium. Surprisingly, a new and large late Roman fortification (c. 3–4 ha), equipped with towers, with a densely occupied interior and ‘extramural’ buildings was also found. The north-eastern curtain was discovered by resistivity surveying, the line of the north-western and south-western sides by intensive survey. Pottery and brick monograms from the new site suggests that it dates to the second half of the sixth or possibly early seventh century. It is argued that the quadriburgium may be the site of ancient Anamon, a station on the coastal road from Thessaloniki to Dion. The newly discovered site, clearly of considerable importance, lay on the north bank of the river Sourvala and probably had direct access to the sea, importing both local pottery and amphorae from the eastern Aegean. Its role may have been to protect the fertile coastline of the Pieria and to provide a secure base for the export of agricultural products to the beleaguered cities and settlements around the Thermaic Gulf.