Its name comes from the outpost reinforcements of the main Castell de la Suda, also named after Sant Joan, which serve as a continuation of it. It is comprised of various interconnected defensive enclosures, built in the 17th and 18th Centuries.
The first enclosure, next to the fort, has the oldest wall to the south of the city, which encompass the medieval Bassa gateway and the site of the access roads between the neighbourhoods of Remolins and El Rastre, and the pedestrian embankment.
The second enclosure or first outpost runs from the glacis down to the ramparts to the north, flanked by watchtowers to the south, On the northern side, we can see the connection to the 14th Century wall with its parapet walk that goes down to the Torre Grossa or Torre del Cèlio, as the tower is known.
The third enclosure or second outpost is formed by a central weapons courtyard flanked by watchtowers that overlook the gullies of El Rastre and El Cèlio.
Weapons courtyard, ramparts or bulwarks, moats, countermures, hornworks, a magazine, embrasures, covered walkways, sloping walls, a ravelin and the isolated stronghold tell us of the functionality and strategic role that the site has had over the years and its status as Tortosa’s stronghold.