Adyton

The adyton (Greek: Άδυτον) or adytum (Latin) was a restricted area within the cella of a Greek or Roman temple. Its name meant "inaccessible" or "do not enter". The adyton was frequently a small area at the farthest end of the cella from the entrance: at Delphi it measured just nine by twelve feet. The adyton often would house the cult image of the deity.

Adyta were spaces reserved for oracles, priestesses, priests, or acolytes, and not for the general public. Adyta were found frequently associated with temples of Apollo, as at Didyma, Bassae, Clarus, Delos, and Delphi, although they were also said to have been natural phenomena (see the story of Nyx). Those sites often had been dedicated to deities whose worship preceded that of Apollo and may go back to prehistoric eras, such as Delphi, but who were supplanted by the time of Classical Greek culture.

In modern usage, the term is sometimes extended to similar spaces in other cultural contexts, as in Egyptian temples or the Western mystery school, Builders of the Adytum.