Made famous by David Farley as the Italian town hiding "the Santissimo Prepuzio, the most holy foreskin, the prepuce of Jesus Christ (and the only piece of flesh Christ could have conceivably left on earth)." David's book, An Irreverent Curiosity: In Search of the Church's Strangest Relic in Italy's Oddest Town, has been released to quite a bit of critical aclaim.
The marker on the map shows the interesting geography around old Calcata or Calcata Vecchia (the outskirts of the new town Calcata are coming into view on the upper right of the map). If you zoom out on the map, you'll discover that Calcata is within the Viterbo province of Lazio, the same region as Rome, which is 29 miles to the south. Calcata is also within the Parco Regionale Valle del Treja; there's a park office in Calcata.
Calcata has been an artist's village since the locals left in the 1930s, fearing the whole thing would crumble into the valley below, so if you like to shop for handmade art, you're in. But what else is there to do in Calcata? According to David Farley in Eight Questions for David Farley, it's not a bad place for walkers:
"I would start off with a walk down in the valley below which is etched with footpaths and littered with tombs from the Faliscans, a pre-Christian people who inhabited the area but were wiped out by the Romans."
I learned of Calcata from a group of expats who live in the Lazio region of Italy. They, and lots of Romans, recommend the weekend trip north to Calcata (weekends are more lively than weekdays).
There isn't a hotel in Calcata, but I Sensi Della Terra rents rooms and houses in Calcata.
More tips for travelers can be found in Farley's own article in Transitions Abroad: Life in an Italian Hippie Hill Town.
Oh, and don't come looking for the holy foreskin, it went missing in 1983.