When describing the Sanctuary of Asclepius in Epidaurus, the ancient author Pausanias, mentions a round building near the temple of Asclepius, which he calls Tholos (i.e. round building) but fails to mention its use. Nevertheless he believes it is worth visiting and describes two murals in its interior, works of painter Pausias from Sicyon. One of them depicted Eros (love) and the second a personification of intoxication drinking from a glass cup.
The Tholos was designed by the architect Polykleitos the Younger of Argos and it is one of the few round buildings of Greek architecture. It was constructed in a period of 30 years, from 365 to 335 BCE. Its exterior colonnade comprised 26 Doric order columns, while the interior had 14 Corinthian order ones. These had the most elaborate and beautiful capitals of the 4th century (which deserved, and got, a post of their own). The metopes (panels above the columns) were decorated with rosettes. The coffers of the ceiling and the front of the roof’s gutter (sima) also bore rich sculptural decoration. Even the floor was impressive, with its intricate pattern of black and white marble tiles.
Floor plan of the Tholos of Epidaurus. Notice the pattern of the floor of the cella, with its rhomboidal tiles of black and white marble. 
The sima (cornice) of the Tholos.
Perhaps the most interesting –and enigmatic– part of the building was hidden from view: it was a basement, under the cella (central chamber), with three concentric walls forming corridors whose use is unknown, although it seems that they were accessed through the cella.
An inscription listing the expenses for its construction names the building as Thymele (which means altar) but also fails to mention its use. Modern researchers have proposed various theories, among which that it was used as a hall for official banquets, as a treasury for valuable offerings to the god or, lastly, as a hall for secret rituals celebrating the god’s connection to the underworld.
According to the site’s current excavators, the Tholos served as the tomb of Aclepius who, according to the myth, was killed by Zeus but later resurrected. However, the basement of the Tholos was on the same level as the basement where patients of the sanctuary went through the last phase of the healing ritual (more about that in another post). That led the excavators to the conclusion that the two basements possibly created a plane where the patients and the god communicated symbolically.
Recently, right next to the eastern side of the Tholos, remains of a predecessor building, which also had a basement, were found.
The Tholos (or Thymele) was destroyed in the 6th century CE and a large part of it was recycled into later buildings. However, enough of its members survived to allow not only for its representation on paper, but also its physical reconstruction.
The latter began in 1984 and continues to this day. The pictures that follow show three different phases of the work, at different times.
Aristotle, Greek tourist guide 
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