The conquest of Borriana by Jaime I Historical milestone · Borriana, La Plana Baixa, Castellón Image of Borriana, not of the place itself. After a long siege with assault towers, the Muslim stronghold capitulated before James I in 1233; it was the first important city won on the Valencian plain and the base from which the advance southwards was organized. 1233 Photo: Xacòina (CC BY-SA 4.0) What to see and do in Borriana