Fortress of Santa Engracia Monument · Pancorbo, Ebro, Burgos Image of Pancorbo, not of the place itself. The fortress of Santa Engracia was built between 1794 and 1797 on the Montes Obarenes to defend the Pancorbo gorge, together with the fort of Santa María, after the War of the Convention against France broke out in 1793. Directed by the engineer Fermín de Rueda, the works produced a complex with capacity for 3,575 people, a hospital, storehouses, powder magazines and cisterns, the largest fortified enclosure in the province of Burgos at the time. Taken by the French marshal Moncey in 1808, after the battle of Vitoria it surrendered to Wellington's troops on 30 June 1813, in what became known as the Siege of Pancorbo. On 23 April 1823 the Hundred Thousand Sons of Saint Louis razed it to prevent liberal troops from being quartered there, and today it is visited in ruins. Photo: Miguel Andrade (Public domain) What to see and do in Pancorbo