The remarkable Osirion at Abydos in Egypt is officially dated to the reign of Seti I, during the New Kingdom period, ruling c.1294 or 1290 BC to 1279 BC. However numerous scholars and researchers suggest it could be much older with its huge megalithic, perfectly cut blocks resembling those in the 4th Dynasty Valley Temple at Giza. Strabo, who visited the Osirion in the first century BC, said that it was constructed by Ismandes, or Mandes (Amenemhet III), the same builder as the Labyrinth at Hawara.
John Anthony West says there were huge floods that occurred in the distant past and the river silt is evident at the site, so could easily be dated. The Osirion at Abydos in Egypt could have had therapeutic effects, according to Dorothy Eady (Omm Sety) who says she got healed by its waters, as did many others. It also has beautiful geometric 'flower of life' carvings on one of the uprights which have yet to be explained, and nubs, polygonal masonry and intricate, subtle striations and smoothing of the stones, which would not look out of place in ancient Peru. Whether it was 'discovered' by Seti, or whether he built it during his reign is discussed in this video.