Ammaia's location on the river Sever was a waypoint on west–east trading routes, linking towns such as Scallabis (Santarém), Eboracum (Évora), Olisipo (Lisbon) and Miróbriga (Santiago de Cacém) to the provincial capital Emerita Augusta (present-day Mérida) via Norba Caesarina (Cáceres). The mountain of Marvão would also have served as a watchtower providing line-of-sight to the vitally-important Roman bridge at Alcántara. Local agricultural production (olives, wine, figs, cattle) was supplemented by horse-breeding, pottery, and mining activity - notably rock crystal and quartz from veins on the Marvão mountain, together with open cast gold mining on the Tagus to the north.[21] Roman Ammaia saw the development of improved irrigation and terracing across the Marvão mountain.