Sozopol's amphitheatre is the main stage of the Apollonia Festival of Arts, which fills the old town at the turn of August and September — the 2026 edition lists more than seventy events and over seven hundred participants — and sends its largest concerts and staged programmes here, while the art gallery, the archaeological museum, the Otets Paisiy community hall and the summer cinema take the smaller ones. The same open-air stage carries the town's summer programme outside festival dates: ABBA Symphonie played there in July 2025 and again in July 2026.