The chief buildings are grouped together, and include temples of Asclepius and Artemis, the Tholos, and the Abaton, or portico where the patients slept.
North of the Tholos is the long portico described in inscriptions as the Abaton; it is on two different levels, and the lower or western portion of it had two storeys, of which the upper one was on a level with the ground in the eastern portion.
The patient consulting the god sleeps in the Abaton, sees certain visions, and, as a result, comes forth cured the next morning.
When the Rhodians regained their freedom they built round this trophy so as to render it inaccessible, whence it was known as the Abaton.