Alconétar Bridge

Alconétar Bridge Puente de Alconétar
Remains of the Alconétar Bridge with its flattened arches
Crosses	Tagus
Locale	Garrovillas de Alconétar, Cáceres Province, Extremadura, Spain
Heritage status	Listed as cultural heritage of Spain
Characteristics
Design	Segmental arch bridge
Material	Stone, Roman concrete
Total length	290 m (950 ft) [incl. approaches]
Width	6.55–6.80 m (21.5–22.3 ft)
Height	Minimum 12.50 m (41.0 ft)
Longest span	15 m (49 ft)
No. of spans	Ca. 18 [incl. flood outlets]
History
Designer	Possibly Apollodorus of Damascus
Construction end	Probably reign of Trajan or Hadrian (98–138 AD)
Alconétar Bridge Mérida Astorga Salamanca Alconétar Bridge with itinerary of the Roman Via de la Plata

The Alconétar Bridge (Spanish: Puente de Alconétar), also known as Puente de Mantible, was a Roman segmental arch bridge in the Extremadura region, Spain. The ancient structure, which featured flattened arches with a span-to-rise ratio of 4–5:1, is one of the earliest of its kind. Due to its design, it is assumed that the bridge was erected in the early 2nd century AD by the emperors Trajan or Hadrian, possibly under the guidance of Apollodorus of Damascus, the most famous architect of the time.

The almost 300 m long Alconétar Bridge served as a crossing point for the Roman Via de la Plata, the most important north-south connection in western Hispania, over the Tagus, the longest river of the Iberian peninsula. It presumably remained in service until the Reconquista, after which numerous early modern reconstruction attempts by Spanish engineers failed. The ruins, which were mainly to be found on the right river bank, were relocated from their original position in 1970 when the Alcántara reservoir was created.

The historic Alconétar Bridge, which should not be confused with the monumental Alcántara Bridge further downstream, spanned the Tagus not far from the mouth of the Almonte, in the heart of the Spanish Cáceres Province in the Extremadura region. A modern motorway and a railway, which cross the Tagus in the immediate vicinity, underline the historical importance of this crossing point between northern and southern Spain. During the building of the Alcántara Dam in 1970, the remains of the bridge were moved from their original site to a meadow six kilometers to the north, close to the municipality of Garrovillas de Alconétar. By contrast, few traces are left of the neighbouring ancient bridge over the river Almonte.