The Bidasoa Basin is a geographical area located in the northeastern part of Spain and southwestern France. It is primarily defined by the Bidasoa River, which flows from the Pyrenees mountains to the Bay of Biscay. The basin is characterized by its diverse ecosystems, including forests, wetlands, and agricultural lands. This region is significant for its rich biodiversity and cultural heritage. The Bidasoa River serves as a natural border between Spain and France, influencing local economies and communities. The basin is also a popular destination for outdoor activities such as hiking, fishing, and birdwatching, attracting both locals and tourists.