The Douro River, known as Duero in Spanish, is a prominent feature of the Iberian Peninsula. It begins its journey in the Soria Province near Duruelo de la Sierra, flowing through the picturesque landscapes of northern-central Spain and Portugal. Along its 897 km length, it passes through regions renowned for wine production, such as the Ribera del Duero in Spain and the Douro Valley in Portugal, which is a UNESCO World Heritage Site. The river's journey culminates at its mouth in Porto, a city celebrated for its port wine and stunning riverside views. The Douro not only supports rich ecosystems and agriculture but also holds cultural and historical significance, shaping the heritage of the regions it traverses.