Peñafiel preserves a 15th-century castle, built by Don Pedro Girón, master of the Order of Calatrava. It has been fully restored and now houses the Wine Museum. Declared a National Monument in 1917, it is one of the most spectacular medieval fortresses in Spain due to its distinctive elongated silhouette, 210 meters in length, which resembles a great stone ship, earning it the nickname "The Ship of Castile."