Biel is a municipality in the province of Zaragoza, within the autonomous community of Aragon in northeastern Spain. It is located in the comarca of Cinco Villas, a historic district in the western part of the province near the border with Navarre.
The municipality formerly included the village of Fuencalderas, which held the status of a "Lower Local Entity" (Entidad Local Menor) within Biel's administrative boundaries. Fuencalderas lies a short distance from the main town and forms part of the same municipal territory.
Biel sits in the foothills of the Pyrenees, in a landscape of rolling hills and farmland typical of the Cinco Villas region. The town preserves a historic core that includes the Church of San Martín de Tours and the remains of a medieval castle, reflecting its long history as a settlement in the Kingdom of Aragon.