File:Sanctuary of Asclepius at Epidaurus - Buildung "E".jpg

English: Referred to as Building E by early excavators, this structure was the first ritual centre constructed on the lower plains at Epidaurus. In the 6th century, it consisted of an ash-altar that accumulated from extensive ritual sacrifice to Apollo and Asclepius. In the 5th century, the ash-altar was enclosed on three sides with the western side open towards the early Square Altar dedicated to Apollo.

The enclosure consisted of long, rectangular porticos to the north and east. The long halls may have been early dormitories and public dining rooms. One small, enclosed chamber on the north-western end was used as a shrine. Excavators found several inscribed 6th century votive offerings to Pythian Apollo and 5th century offerings to Asclepius within the ash-heap. During the period of monumentalisation in the 4th century, Building E was modified. The small shrine was re-built in limestone and a low altar-table added. The floor slabs were cut with a channel to allow for water drainage for cleansing the room. The southern wall was converted into an additional enclosed rectangular room. The open, western side was embellished with a propylon with slender columns. The inner ash-altar was formalised with a stepped wall to preserve the ash and votive offerings over centuries of worship. Prior to the massive expansive of the Sanctuary in the 4th and later centuries, Building E is likely to have been used as a combination of temple, altar, hestiatorion, and abaton. It would have fulfilled each of the roles of worship, ritual dining, and overnight incubation for those seeking healing at the sanctuary prior to the site’s expansion.

The arrangement of the early temple and altar remain clear, although only the lower foundations and partial walls remain. The lower walls of the narrow rectangular rooms on the northern, eastern, and southern sides remain standing up to about a metre in height. The outline of the enclosed shrine and its paved floor is also visible. The western propylaia is seen by the fragments of columns and enclosing wall. To the north are the remains of semi-circular stone benches from a later date.