Kalithea is located about 8Km (4,970mi) from Rhodes Town on the east coast of the island. The Bay of Kalithea has long been famous for its healing waters that sprang from the surrounding rocks. This miraculous spring has been known since the time of the Doric Hexapolis and the age of Knights and even beyond the limits of the island The inhabitants from across the coast of Asia Minor and father deep in Anatolia came to visit the spring of Kalithea and stay there a long as it was necessary, especially in the clement month of September.
An extensive study of the waters began in 1927, while Rhodes was under Italian occupation. The results of the study proved that the specific waters at Kalithea Bay have a range of important properties, thus the development of the area was proposed. The famous architech Pietro Lombardi was appointed to plan the Thermal Spa Institution in 1928. His plans for the Kallithea Thermal Spa were considered among the best architectural compositions of the time.