Astronomical Orientation of Ancient Greek temples to solar/moon/star rissing/setting targets is an old subject (Penrose 1892. Nissen 1906-1910. Dinsmoor 1939), that still preoccupies many recent studies on Archaeoastronomy (Papathanasiou and Hoskin 1994. Papathanassiou & Papadopoulou 1997; Aveni and Romano 2000; Liritzis & Vasiliou 2002, 2003, 2006; Vassiliou, 2007). A main factor to the determination of the orientation of those temples is the date of the festivals celebrated in situ in honor of their divine owners. In reality, apart from the festivals with a fixed date, epigraphic evidence implies existence of local homonymous festivals with various and maybe movable dates, including seasonal rites associated to the agricultural year and celebrated in honor of Demeter, the chief deity of agriculture (Kravaritou 2006, 2007). Our problematic is oriented towards the eventual impact of this fact to the orientation of Demeters’ temples. Here we provide new evidence based on measurements of 15 monuments attributed to Demeter at Eleusis, Athens, Thebes, Delphes, Eretria, Corinth, Delos, Tenos, Thassos, Mytilene, Kos, Rhodes, Knossos, Andros, and Sicily, that date to various historical periods and provide literary evidence attesting local celebrations. Those measurements are cross-examined in relation to bright stars –including whole constellations- whose rising/setting determined according to ancient texts the main agricultural works. Azimuth Values, angular altitude of skyline, and geographical coordinates were measured by magnetic compass, a clinometer, a theodolite and a GPS, and comparison was made with measurements obtained by other scholars. In the interpretation, use was made of the SkyMap Pro10. The question of the orientation of Greek temples is actually revisited, on the basis of investigating the impact and the eventual interference of both local festivities and panhellenic customs (cf. annual agricultural works) to the astronomical orientation of the temples of one single divinity, the Demeter. Bibliography A. F. Aveni & G. Romano, « Temple Orientation in Magna Grecia and Sicily », Journal for the History of Astronomy 31, 2000, 52-57. W. B. Dinsmoor, “Archaeology and Astronomy”, Proceedings of the American Philosophical Society 80, 1939, 95-173. S. Kravaritou, La configuration des calendriers des cités grecques. Temps du rituel et temps du récit, Unpublished Ph.D. Thesis, Paris/Lausanne 2006. S. Kravaritou, (2007) “Greek ‘Calendars’ and symbolic representation of the cosmic order: seasonal rites for Demeter”, Mediterranean Archaeology and Archaeometry, Special Issue, Vol.6, No 3 (in press). I. Liritzis & H. Vasiliou, “Astronomical Orientations of Ancient Temples at Rhodes and Attica with a Tentative of Interpretation”, Mediterranean Archaeology and Archaeometry 2(1), 2002, 69-79. I. Liritzis & H. Vasiliou, « Archaeoastronomical Orientation of Seven Significant Ancient Hellenic Temples », Archaeoastronomy 17, 2002-2203, 94-100. I. Liritzis & H. Vasiliou, « Were Greek temples oriented towards aurorae ? », Astronomy & Geophysics 47, 2006, 14-18. H. Niessen, Orientation. Studien zur Geschichte der Religion, Berlin 1906-1910. M. Papathanassiou & M. Hoskin, “Orientation of the Greek Temples on Corfu”, Journal for the History of Astronomy 25, 1994, 111-114. M. Papathanassiou & Z. Papadopoulou, “Orientation of the Greek temples on Delos”, Proceedings of the 6th European and 3rd Hellenic Astronomical Conference, held in Thessaloniki, Greece, 2-5 July 1997 . F. C. Penrose, “A preliminary statement of an investigation of the dates of some of the Greek temples as derived from their orientation”, Nature 45, 1892, 395-397. Vassiliou, H 2007, PhD thesis, Dept of Mediterranean Studies, University of the Aegean, Rhodes.