Sprawling ancient city walls thread their way up the hillside high above the modern double harbour of Limenas Town to the hilltop ruins of a castle and Acropolis.
The extensive ruins are scattered along a narrow terrace that runs the length of a crescent ridge nearly 140 metres above the Thassos port capital of Limenas.
The steep wood-carpeted bluff, crisscrossed with defensive walls, offered former islanders a good hideaway to escape marauding pirates as a well as providing a natural look-out post over the sea to the mainland at Keramouti.
The remains are pretty widely spread out over the hillside so holiday visitors to Thassos should pack a few provisions if they want to visit all the sites.
On the higher levels are the remains of ancient temples to Athena and Pan while the lower level has an impressive Roman amphitheatre that once accommodated 3,000 spectators.
The impressive amphitheatre is the first sight to greet walkers as they climb the hill from the port. Set in a natural curve in the rock, it is thought to date from the 5th century BC.
Several features were added in the 3rd century BC and excavations have shown that the site was given a major makeover by the Romans in the 1st century AD.
Tiers of stone seats are arranged in a semi-circle up the hillside overlooking a large circular stage arena backed by a line of pillars.
Some of the seats have Latin names carved into the stone; they were perhaps reserved for wealthy or influential Romans who had enough clout to bag the best seats on a permanent basis.
Large upright marble slabs set around the edge of the stage suggest that spectators may have needed protection, presumably from wild animals and there is evidence that the Romans used the arena for gladiatorial combat.
Panoramic views of the town and harbour are impressive and the theatre makes a magnificent setting for the musical concerts and plays that are still often performed today.
Woodland takes over as the visitor ascends the hill to the extensive if scattered ruins of a former castle. Only a few structures remain among the terraced walls.
Work on the castle started in Byzantine times and completed in the 15th century by the Genoese ruling family of Gattilusi. The remains of a couple of fortress towers and a church lie within the castle area.
The ruins of encircling houses suggest that Thassos islanders may have lived here as late as the 17th century, presumably to avoid the attention of pillaging pirates.
The next terrace up the steep bank leads to the ruins of a former temple to Athena dating from the 5th century BC. There is not much to see now as many of the marble slabs that made up the temple were pillaged to build the walls of the castle and only the foundations remain.
The path climbs even higher to the highest terrace where a cave set in the hillside is thought to have once contained a sanctuary dedicated to the Greek god Pan.
Carved into the rock inside is a relief that appears to portray the goat-legged Greek god stretched out lazily while playing his flute. The name Pan originates from the Greek 'paein' meaning pasture and, as well as being the Greek god of fields and wilderness, he is also strongly associated with fertility.
Many tales of Pan in Greek mythology tell of the god's erotic adventures and some visit the cave of Pan in the fond hope of greater sexual prowess and fertility.