Built in the 18th century by King João V in fulfillment of a vow to obtain succession from his marriage to D. Maria Ana of Austria or the cure of a disease he suffered, the National Palace of Mafra is the most important monument of the baroque in Portugal. Constructed in lioz stone of the region, the building occupies an area of nearly four hectares (37,790 m2), comprising 1200 divisions, more than 4700 doors and windows, 156 staircases and 29 courtyards and lobbies. Such magnificence was only possible because of the gold of Brazil, which allowed the Monarch to put into practice a policy of patronage and reinforcement of royal authority.