The gate takes its name from its proximity to a temple dedicated to Mars, the Roman god of war. This monument, built between the 2^nd and 3^rd centuries, is the longest arch in the Roman world : 6.4 m high by 32.4 m long. It gave access to the Gallo-Roman town of Durocortorum. It is made of three arches on which original sculptures are still visible : Romulus and Remus, the farm works, Leda and the swan.

Listed as a Monument Historique in 1840

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