|Summary:||Circular building; southwest of the Temple of Asklepios, in the central Sanctuary of Asklepios.|
|Date:||ca. 360 BC - ca. 320 BC|
Stylobate diameter: ca. 21.3 m; labyrinth diameter: 13.36 m.
Circular building with outer colonnade of 26 Doric columns and inner colonnade of 14 Corinthian columns. Leading to the east entrance, which had windows at either side, was a ramp over the three-stepped platform. Beneath the floor of the Tholos was a labyrinth reached by a hole in the center of the floor.
Also known as the Thymele, the activities of the cult of the Hero Asklepios took place here, and the labyrinth below may have housed sacred snakes. Pausanias wrote that Polykleitos the Younger was the architect. The building had elaborately carved architectural elements and fine paving of black and white limestone. Dinsmoor states that the paving was marble.