Castillo de Olmillos de Sasamón is a 15th-century fortress-palace built in 1446 by Pedro de Cartagena, an alderman of Burgos, in the province of Burgos, Castile and León. Rather than a defensive stronghold, this elegant structure was designed as a recreational and vacation palace, featuring a rectangular floor plan with perfectly preserved circular towers at each corner crowned with circular machicolations. The castle belonged to the Cartagena family during the 15th and 16th centuries before passing through the hands of various noble families including the viscounts of Valoria and the dukes of Gor. On July 22, 1812, Spanish guerrillas led by Santos Padilla set the castle ablaze as a symbol of resistance to French occupation. Today, fully restored and privately owned, it operates as a hotel, welcoming guests to experience its historic elegance and architectural heritage.