There was an article in Scientific American over ten years ago about Sybaris. It is on south side of "great toe" of the
Italian boot. It was on a river, with a harbor much used by
traders, some of whom sailed up the river and landed goods
rather than go between Scylla and Charybdis.
There was enough trade that the city oot rich. But the river and harbor silted up, and the city died. The story about their horses dancing to music played by attacking
enemy is probably a fable.