The sanctuary for (Zeus) Lycaios at the top of Mount Lycaion bears witness to very primitive rituals and a story of creation that is very different from that of traditional mythology. Originally worshiped by primitive Arcadians was a god Lycaios, the “spirit of the wolves”. In order to ward off his anger (and thereby raid the sheep), a baby was regularly offered (once a year?) On top of one of the higher mountains of Arcadia. For the Arcadians, the man who had begun that was the first person, Lycaon. His name betrays that he was seen as the son of this wolf god. He was also the ancestor of all Arcadians. In Pausanias it can be read between the lines that these sacrifices were still held in historical times (with the civilized, classical Greeks!), Even though the sanctuary in its time had fallen into disuse and was partly demolished. On top of the mountain stood an altar for the supreme god (Zeus) Lycaios, with next to it two columns, on top of which were two golden eagles (clear evidence that the classical Arcadians had now identified their supreme being Lycaios with Zeus), with a high conical behind it hill built from the ashes of the victims for Lycaios. By the time of Pausanias, the eagles had already been taken to Megalopolis, which you can see lying deep in the plain from the top.
Nowadays the site is especially worth it because of the view over Arcadia and the thought of the horrible rituals that have taken place there. During excavations at the foot of the (now disappeared) ash hill, the column bases and the altar for Zeus Lycaios have been found. The site is well signposted and easily accessible by car. Walking up (or driving) from the lower sanctuary for the god Pan (also such a typical Arcadian and primitive shepherd deity), which is currently again the subject of excavations, you have a good view of the horse track (Hippodrome) that was used in the annual Lycaia games.
Images: from left to right the sanctuary for Pan, the Hippodrome, a column base next to the altar for Zeus Lycaios.