The Gothic Cathedral we have today was built on the foundations of the primitive paleo-Christian basilica and the subsequent Romanesque Cathedral. Construction commenced on 1 May 1298 during the mandate of Bishop Bernardo Pelegrí and the reign of King James II of Aragon, the Just, and was virtually completed by the mid-15th century, under the mandate of Bishop Francisco Clemente Sapera and the rule of King Alfonso V of Aragon.
Three distinct periods can be defined within the 150 years of construction: in the first, the building was planned and the apse and radial chapels were built, as were the presbytery - with its altar and crypt- and the pseudo transept; afterward, the three naves, with their respective lateral chapels, were extended back to the choir; finally, construction of the basilica continued to the façade, which was later closed with a simple wall (1417). The Cloister was finished in 1448.
At the end of the 19th century, the Barcelona industrialist Manuel Girona Agrafel offered to undertake the work on the façade and on the two side towers, in keeping with the plans drawn up by the architect Josep O. Mestres and inspired by the initial 15th-century project. Mr Girona's children finalized their father's work in 1913 on completion of the cimborio. [source]