Castellany of the Order of the Hospital Historical milestone · Amposta, Montsià, Tarragona Image of Amposta, not of the place itself. Ramon Berenguer IV donated the castle of Amposta to the Order of the Hospital in 1149 and the town became the head of the castellany that grouped its domains in the Crown of Aragon. The stronghold controlled the crossing and the mouth of the Ebro. 1149 Photo: Judesba (CC BY-SA 4.0) What to see and do in Amposta