The present monograph is the first to provide a detailed overview of the cults of gods and heroes in the regions of Elis and Triphylia in the western Peloponnese from the Geometric to the Roman Imperial period. Due to the great abundance of evidence from the Panhellenic sanctuary of Olympia, only those cults from there could be taken into consideration that were also present in the city of Elis, the urban center of the homonymous polis. The systematic evaluation of all available archaeological, epigraphical, literary and numismatic evidence results in a comprehensive picture of the sacred topography of the aforementioned regions. Special attention is paid to the manifold cultic interconnections between the city of Elis and Olympia, the most important extra-urban sanctuary of the polis. These links were the result of a cult policy actively pursued by the Eleans, which was not limited to Olympia but also extended to Triphylia where Elis was the dominating power for longer periods of time.