Biert, a small town of Upper Couserans is located in the Regional Natural Park of the Pyrenees. The village, situated 600 meters above sea level, is on the banks of the Arac and is dominated by two limestone spurs said Ker of Massat and Ker Biert, contrasting with the surrounding granitic and schistose massifs such as the Peak of Three Lords (2199 m) which dominates the massatois basin which marks the border between the Atlantic world and the Mediterranean world. In a previous census, the town had a population of Biert 300 inhabitants, while in 1851, date of its establishment as a separate town in the municipality of Massat, it had 2,565.
Joint Regional Natural Park of the Pyrenees, it is located in a pleasant green valley that of Massat in Haut-Couserans.
The main feature of the biertois habitat is being scattered settlements: most of the population live in biertoise heights.
The common Biert claims a rural preserved living environment and quality of life in the mountains. Certainly the modern world has changed the rural life but the location since the 1970s of an urban population wanting a new way of life has revitalized this valley. Moreover, the continuation of farms by young farmers has protected agricultural land. Other activities (beekeeping, cider, wood) exist in the municipality.
