In the three centuries following the birth of Christ, Juliomagus (the Roman city of Angers) extended across a vast area above the left bank of the river Maine. On the site where Saint-Martin subsequently developed, a north-south road existed, flanked to its east by houses of earth and timber, and to its west by larger masonry structures. In the face of increasing threats, towards the end of the third or beginning of the fourth century, the city retreated behind a wall. The urban area so defined was effectively reduced to nine hectares.
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