Growing up in the suburbs of Atlanta, he spent a year at Florida State, kept passing a 'See the World, U.S. Navy' sign in Tallahassee and enlisted as an operations specialist. Asked where to go, he said anywhere, and was sent to Italy at 19, where within 24 hours he loved it.

At the NATO base in Naples he heard locals whisper about an Atlantis near Pozzuoli and Baia. He hired a fisherman and boat, saw walls in the water when the sun came out, dived to about nine or ten feet, cleared debris and found a Roman mosaic floor.

After a couple of years of research he found it was built by Agrippa, the right-hand man of Octavian, who became the emperor Augustus. It is the same Agrippa whose name is on the Pantheon in Rome. Bradyseism, land rising and falling over magma, put much of the area underwater.

Walker explains bradyseism, the rising and falling of the landmass due to magma underneath, which the area has a lot of. Locals pieced together stories, such as Emperor Nero's palace being there, where he tried to kill his mother, and many more walls than a single palace.

He says all three are magnificent and must be visited, but calls them a repository of culture while the other 99% of Italy lies beyond them. Going further requires doors opened through relationships he has built over 35 years, such as meeting a living descendant of Frederick II in Palermo.

Called Stupramundi, the wonder of the world, he spoke several languages, and his court was where Italian was first truly spoken, before Dante. He was Holy Roman Emperor, king of Sicily and king of Jerusalem, and wrote a book on falconry used until the 20th century.

Gaida, named after the nanny of a Trojan hero, a fishing village with a castle; Castel del Monte in Puglia, Frederick II's hunting lodge; and the grotto of the Archangel Michael on the Gargano Peninsula, a major medieval pilgrimage site that was a sacred pagan grotto even before Christianity.

In northern Calabria, the large cave has a 20,000-year-old bull painting on a boulder at its edge and, inside, an 11,000-year-old couple buried in an embrace. Walker went before signs and plaques existed and expects it to be on the map soon, near popular Tropea.

After about 20 years in South and North America, including running a company in Rio de Janeiro, he calls leaving Italy the biggest mistake of his life. He and his Italian-Brazilian wife will base themselves in Perugia in Umbria, near 40 to 50 hilltop towns and 15 minutes from Assisi.

Buried Italy, on Amazon, shows that what is buried in Italy is still alive through its people and stories, 'buried but still alive'. It covers southern Italy and Sicily before mass tourism, including meals and conversations with locals. Extras are at italianhistorywithjoseph.com/human, including field notes and an unpublished chapter.