A Hellenistic theatre cut into the hillside above the ancient agora, with surviving marble seating and a well-defined stage area. The structure is in good condition for its age, and in summer it is used for live performances — ancient drama, concerts, and occasional film screenings — under an open sky. Watching a performance here, with the port and the Kavala coastline visible beyond the stage, is one of those experiences that makes Greek archaeology feel genuinely alive rather than simply picturesque.
From the upper rows the view down to the port and across to the Macedonian mainland is excellent. Even without a performance, it is worth climbing up from the agora simply to sit in the seats for a few minutes and take in the geography. The theatre is a short uphill walk from Thassos Town and signposted from the main road through the ancient site.