Source of the Barcala River Nature · Santa Comba, Xallas, A Coruña Image of Santa Comba, not of the place itself. The Barcala river, a right-bank tributary of the Tambre, rises on Mount Fontemago, near Fontecada, within the municipality of Santa Comba, which gives its name to the neighbouring Xallas comarca. It soon leaves this municipality to flow through A Baña and Negreira, where it empties into the Barrié de la Maza reservoir, already on its way to the Tambre basin. Along its course it gathers the waters of numerous rivulets and minor streams flowing down from the lands it crosses. Photo: Miguel Branco (CC BY-SA 4.0) What to see and do in Santa Comba