This castle is variously known as El Castellet or the Castell de Castells de Serella
It is located on a rocky outcrop (Penya del Castellet) on the crest of the eastern arc of the Sierra Serella (1050 m). It has extensive views in all directions. To the north it overlooks the valley and village of of Castell de Castells, with glimpses of the sea in the distance; to the south the valley and village of Guadalest and the sea at Albir can be seen.
The bulk of the Serella mountain range runs westwards, and the sites of further Islamic remains can be seen, including the lookout of Pla de la Casa.
Little is known of its early history, the first record of the castle was in the in the Treaty of the Well 1244-1245.
The fortification, which was named as Castell (Qastâl) and its associated lands, including various farmsteads such as d’Aialt, Bitla and Espelda was ceded to Al Azraq for his use for three years. It was taken by King Jaume in 1250 and abandoned soon after the Christian reconquest.
The fortification is built almost entirely of tapia and consists of two distinct areas. The highest point consists of a small plateau where there is a rectangular tower (A), some remains of walls and a water cistern (B). This would have been the celoquia where the caid lived. The ruined tower walls still stand to a height of about 4m. This area can only be reached by scrambling up steep rocks. The lower albacar ( walled refuge) is a large space which lies on the northern slopes, bordered by a low wall
which can be seen in sections. It has a well-preserved water cistern (G) which retains water to this day and is located next to the entrance to the enclosure.
The castle has not been excavated and it is not known exactly when it was built, but ceramics found on the surface indicate a date from the second half of the 11th century. Like most of the other Marina Alta castles it is protected by the 1985 Law (Ley 16/1985) on Spanish