showed me some fossils of sea

That's because there wasn't much information about the trails, nor about the Etruscan civilisation that built them. The ancients didn't leave road maps or written records, and many pathways were abandoned and overgrown with shrubs. But in the last few decades, archaeological discoveries in tombs across central Italy, and as far as Corsica, have revealed more about the Etruscans and their mysterious vie cave, which are said to connect the land of the living with the land of the dead.