Villalba Castle is also known as Cebolla Castle or Malpica el Viejo Castle (meaning Old Malpica Castle). It lies on a hill surrounded by an orchard of (I guess) olive trees and next to the crossroads of the 4000 road from Toledo to Talavera de la Reina and a smaller road leading north to the village of Domingo Pérez, in the province of Toledo in Spain.
The oldest reference to this castle dates back to the time of the Knights Templar, in the 10th and 11th century, who also owned the nearby castles of San Servando an Montalbán. It probably was built on Roman remains. Later on it was owned by Lopez de Ayala, the counts of Oropesa and the Dukes of Frías.
The castle has a rectangular groundplan. In its corners were towers which, nowadays, have disappeared. All that remains at the present are the curtain walls, some with square towers in their center, of which the largest one probably served as a keep.
The castle is of concrete, constructed according to the Muslim technique. There are vestiges of buildings in the interior of the castle. And outside there is some evidence of a former moat and an outer enclosure.
The castle ruins are freely accessible. This is a very deteriorated ruin which makes it hard to see much architectural detail. However it's a nice walk to the castle and there are nice views of the surrounding land from the top.
Also in the middle of the interior of the castle was a small, recently planted, olive branch. A note hanging of a little fence that guarded it, said that it was planted by a widow in memory of her dead husband. It didn't say why she had planted it here but it was moving.