Counted among the minor Etruscan cities by Plinio, and remembered by Strabone and Tolomeo, Blera is situated on a narrow, winding and tufaceous piece of headland that is 1500m long. It is divided by three ditches from the sides of which flow the waters of the Rio Canale and the Biedano. The modern urban area has a typical medieval part in the eastern region, the remaining area (Petrolo), is nowadays partly deserted and is more agricultural. It has modest remains of walls, traces of the consular Via Clodia that crossed it and an articulated system of disposing water using wells and underground passages.
The consular Via Clodia that on reaching Barbarano Romano, went through the town is still clearly visible as can be seen in the road lay out, in the cut tuff. Above all, are the monumental remains of two bridges in square tuff blocks: that of the Devil (end of first century and beginning of the second B.C.) with its three arches that went over Biedano in the south - east and Rocca, under the top of the plain, and by a single arch on the Rio Canale in the north-west, (7.50 m high) considered to be the oldest for more than a decade. Also of extreme interest is the technique used in consutrction and the numerous tombs that surround the out of town tracts of the Clodia that go from the top to the bridge.
Blera developped during the VIII cent. B.C. and reached its peak as regards agriculture and commerce in the VI century. However, archeological proof states a perseverance up until the first century B.C. This century-old vitality originated in the vast necropoli that occupied in a rational order the sides of the surrounding rocks. Over the centuries a continued use of the land agriculturally clearly shows all the typical aspects of the Etruscan tombs, from ditches to tunnels, from chamber tombs to hypogean names and huge vaults. The most important and interesting centres submerged in thick vegetation are at Ponton Graziolo, at Terrone, at Pian Galiardo, at Saint Barbara and in particular at Pian del Vescovo. In the necropolis of the Casetta in a conspicuous number of rocky cubed shaped tombs is the so-called "Penta cave". It is Blera’s jewel. With its great chamber and a pillar in the centre, the base and top of which are covered in tuff like the walls with traces of paintings like the classic sequence of stylized waves.