The Arena of Nîmes is a Roman amphitheatre built around AD 70. It was remodelled in 1863 to serve as a bullring. The Arenas of Nîmes is the site of two annual bullfights during the Feria de Nîmes, and it is also used for other public events. The building encloses an elliptical central space 133 m long by 101 m wide. It is ringed by 34 rows of seats supported by a vaulted construction. It has a capacity of 16,300 spectators.
As the Roman Empire fell, the amphitheatre was fortified by the Visigoths and was surrounded by a wall. During the turbulent years that followed the collapse of Visigoth power in Hispania and Septimania, not to mention the Muslim invasion and subsequent conquest by the French kings in the mid eighth century, the viscounts of Nîmes constructed a fortified palace within the amphitheater. In 737, after failing to seize Narbonne, Charles Martel destroyed a number of Septimanian cities on his way north, including Nîmes and its amphitheatre, as asserted in the Continuations of Fredegar. Later a small neighbourhood developed within its confines, complete with one hundred denizens and two chapels. Seven hundred people lived within the amphitheatre during the apex of its service as an enclosed community. The buildings remained in the amphitheatre until the eighteenth century, when the decision was made to convert the amphitheatre into its present form.
References:The Gravensteen is a castle in Ghent originating from the Middle Ages. The name means 'castle of the counts' in Dutch. Arnulf I (918–965), Count of Flanders, was the first to fortify this place, building a medieval bastion on this high sand dune, naturally protected by the river Leie and its marshy banks. This bastion consisted of a central wooden building and several surrounding buildings, also in wood.
In the early 11th century, the wooden building was replaced by a stone residence, consisting of three large halls that made up three storeys, connected by a stone stairwell. The monumental stone staircase, the light openings, the fireplaces built into the walls and the latrines were signs of considerable luxury and comfort in those days. There was probably also a tower.