The Tours amphitheater (also known as the Caesarodunum amphitheater) is a Roman amphitheatre located in the historic city center of Tours, France, immediately behind the well known Tours cathedral. It was built in the 1st century when the city was called Caesarodunum. It was built atop a small hill on the outskirts of the ancient urban area, making it safe from floods, convenient for crowds and visitors, and demonstrating the power of the city from a distance. The structure was an enormous, elliptical structure approximately 122 meters by 94 meters. According to its design it is classified as a "primitive" amphitheatre. Unlike the famous Colosseum that was made mostly of masonry and built above-ground, the Tours amphitheatre was made mostly of earth and created by moving soil and rock into a bowl shape. Spectators likely sat directly on the grassy slopes, while the masonry was primarily used for the vomitoria and retaining walls.
When it was expanded in the 2nd century (to 156 m X 134 m), it became one of the largest structures (among the top ten) in the Roman Empire. It is not clear why the amphitheater was expanded given the population and slow growth of the city at the time. About a century later, this expanded amphitheatre was transformed into a fortress, with an addition of a rampart style wall, typical during the decline of Roman Empire. It gradually fell into ruin during the Middle Ages and canonical houses were built upon it and gradually concealed it. The vomitoria were at some point transformed into cellars.
The amphitheater was then completely forgotten until the 19th century, when it was rediscovered (1855). Evidence such as the layout of the streets and radiating lots of the district drew attention to its existence. Surveys and terrain analyses in the 1960s gathered further data on the cellars of the houses which were previously built on the amphitheater walls. Over the past decade, more in-depth studies of the topography and architecture have taken place and are changing the theories and opinions surrounding this monument.
The remains of the amphitheater are not protected as historic sites directly; however, some of the houses built upon it are registered as historical monuments. The ruins of the amphitheater are significant as they are among the oldest known ruins in the city and offer clues about the early history and development of the area.
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