On the northern slopes of Peristeri Mountain (Lakmos), Gradetsi (castle) dominates the limestone ridge, with an altitude of 1306m, accessible mainly by the eastern side. The south and west sides are the most rugged, while the north is strongly sharp. The precinct has a maximum length of 530m, width of 125-220m, spread of 1350m and it includes an area of 8.15 hectares. The thickness of the wall varies from 1.30m on rocky points to 2.00 - 2.20m on the most accessible spots. On the north side of the castle, the original wall thickness of 1.50m was expanded in a second phase with internal addition (2.40m).

The wall seems like a heaped stone pile, built with stones crushed due to the stone quality and the frost prevailing there in winter time. The interior is dominated by the two walled peaks, which are two separate citadels, while many ruins of buildings exist. Some are curve-shaped, just like the traditional buildings of Vitsa, while others rectangular-shaped with two rooms. Throughout the whole area roof tiles and unpainted shells of the Hellenistic period are observed. West to the gate, on a flat surface a well –in use since ancient times- offers visitors its cold water.

Pilot surveys performed at the east side of the castle showed the existence of metallic ground layers. There, some coins were discovered, dating from the 4th century to the late Roman and Byzantine times. The dating of the northern citadel with the tower as well as the bastion and the eastern addition at the south citadel with two towers is estimated at the Hellenistic period.

Most likely the castle wall was built until the beginning of the 3rd century BC, when King Pyrrhus was seriously concerned with the defense of the country. The position of the settlement was one of the most important, as it could control the passage to Thessaly through Metsovo - Zigos. The size and location of the settlement, the physical and technical fortification with two citadels, near a region rich in mineral resources and explosive rocks (ash-green granite), reveal the importance of the largest stockbreeding village of ancient Epirus.

Probably, in this place the ancient (and prehistoric) Trampya existed, near Vouneima, indirectly related to the Homeric tradition. The exact position of Vouneima should be researched at the two nearby villages “Anthohori” or “Votonosi”.