hot water-wheels was widespread in Roman mines.
Middle Ages
Arles was badly affected by the invasion of Provence by the Muslim Saracens and the Franks, who took control of the region in the 8th century. In 855 it was made the capital of a Frankish Kingdom of Arles, which included Burgundy and part of Provence, but was frequently terrorised by Saracen and Viking raiders. In 888, Rudolph, Count of Auxerre (now in north-western Burgundy), founded the kingdom of Transjuran Burgundy (literally, beyond the Jura mountains), which included western Switzerland as far as the river Reuss, Valais, Geneva, Chablais and Bugey.
In 933, Hugh of Arles ("Hugues de Provence") gave his kingdom up to Rudolph II, who merged the two kingdoms into a new Kingdom of Arles. In 1032, King Rudolph III died, and the Kingdom was inherited by Emperor Conrad II the Salic. Though his successors counted themselves kings of Arles, few went to be crowned in the cathedral. Most of the territory of the Kingdom was progressively incorporated into France. During these troubled times, the amphitheatre was converted into a fortress, with watchtowers built at each of the four quadrants and a minuscule walled town being constructed within. The population was by now only a fraction of what it had been in Roman times, with much of old Arles lying in ruins.
The town regained political and economic prominence in the 12th century, with the Holy Roman Emperor Frederick Barbarossa traveling there in 1178 for his coronation. In the 12th century, it became a free city governed by an elected podestat (chief magistrate; literally "power"), who appointed the consuls and other magistrates. It retained this status until the French Revolution of 1789.
Arles joined the countship of Provence in 1239 but suffered its prominence being eclipsed once more by Marseilles. In 1378, the Holy Roman Emperor Charles IV ceded the remnants of the Kingdom of Arles to the Dauphin of France (later
