The castle’s ruins were classified as a National Monument in 1928. Its origin is thought to date back to the Muslims or Leon. Presumably, the second castle came from the rebuilding of the first in the reign of King Dinis, in the late 12th century. It is in Gothic style and covers no more than 100m. It is actually considered one of the smallest in the border area. It was altered again during the reign of King Manuel I based on a design by Francisco Danzilho. The 18th century alterations turned it into a munitions and gunpowder dump. On 26 August 1810, during the siege in the third French invasion, the castle was practically destroyed by an explosion, making it the ruin of the old castle once built by King Dinis.