Artefacts discovered in the region of Chaves identify the earliest settlement of humans dating back to the Paleolithic. Remnants discovered in Mairos, Pastoria and São Lourenço, those associated with transient proto-historic settlements and castros, show a human presence in the Alto Tâmega dating to the Chalcolithic. The region has seen persistent human settlement since Roman legions conquered and occupied the fertile valley of the Tâmega River, constructing a nascent outpost and taking over the existing castros in the area. The settlement was located at the convergence of three important Roman roads: the Bracara Augusta, Asturica, and Lamecum that crossed the Roman Province of Gallaecia, linking Rome to the region's natural resources. It was a military centre known for its baths, which lasted until the 16th century. This civilization constructed protective walls to protect the local population; spanned the river with the bridge; promoted the baths (with its warm medicinal waters); exploited local mines and alluvial deposits and other natural resources. Its importance led to the urban nucleus being elevated to the status of"municipality" in 79 AD, during the reign of the first Flavian Caesar, Titus Flavius Caesar Vespasianus Augustus. Its benefactor consequently influenced its toponymy, becoming known as Aquae Flaviae. Artefacts from the area around the Matriz church indicate that Aquae Flaviae's centre was located in this place, in addition to an ancient headstone showing gladiatorial combat.