Civita di Bagnoregio was founded by Etruscans more than 2,500 years ago. The Civita (or City) was the birthplace of Saint Bonaventure, who died in 1274. The location of his boyhood house has long since fallen off the edge of the cliff. By the 16th century, Civita di Bagnoregio was beginning to decline, becoming eclipsed by its former suburb Bagnoregio.
At the end of the 17th century, the bishop and the municipal government were forced to move to Bagnoregio because of a major earthquake that accelerated the old town's decline. At that time, the area was part of the Papal States. In the 19th century, Civita di Bagnoregio's location was turning into an island and the pace of the erosion quickened as the layer of clay below the stone was reached in the area where today's bridge is situated. Bagnoregio continues as a small but prosperous town, while the older site became known in Italian as La città che muore ("The Dying Town").
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the entrance to the city is quite spectacular as you can only enter through a narrow bridge that leads to the city on the top of the tufo plateau.
It is not a strenous walk and your efforts are rewarded by the sight of the old city and the spectacular views.