This article investigates the agency of the architecture of the Temple of Apollo at Claros and its cognitive impact on the ritual of divination. In the comparison with Delphi, Claros represents a peculiar example of how architecture evolved to suit and shape at the same time the ritual it was hosting. The paper starts with the analysis of the exteriors of the building, highlighting the choice of the Doric style dictated by the desire of being associated to Delphi. A further (...) analysis of the internal layout gives the author a chance of describing the cognitive inputs that the peculiar structure sent to the ancient mind. Specifically, the paper studies how the narrow tunnels made of black marble that turned seven times and the underground cave like adyton created a situation of sensory confusion in the mind of the seekers and the oracle that found themselves prone to detect agencies in the surrounding space and specifically to identify the agent with Apollo. (shrink)