The ancient city at Platiana occupied a tall, elongated hill on Mount Lapitha, south of the Alfeios River. It was divided into three parts: the acropolis, or upper city, on the hilltop, the lower city on the south slopes of the acropolis, and a third zone on the north slope. All three parts were protected by walls.


The acropolis is a typical example of a naturally fortified site with added man-made fortifications, which enclosed both private and public buildings. Within the enceinte are eight terraces, now covered with architectural remains of the Archaic, Classical, Hellenistic, and Roman periods. The acropolis proper occupied the highest terrace, at the west. The enceinte of polygonal masonry survives to an impressive height. Built in the Late Classical and Hellenistic periods, it had a number of towers and gates.

The upper city's four lower terraces (I-IV), on the east, were probably occupied by private residences and public buildings. Recent excavations on terraces III-IV revealed a large rectangular building with five rooms, a possible workshop with two rooms and a courtyard, and a single-roomed building, all of the Late Classical and Hellenistic periods. The agora was probably located on terrace V, where a large square water cistern survives to this day. Parts of the stage and cavea of a small theatre built of roughly hewn ashlar blocks of local limestone occupied terrace VI. Terrace VII, at the very top, was given over to the acropolis proper, which had its own fortification wall, a water cistern, and a well. Terrace VIII, on the hill's west end, has no architectural remains.