The foundation stone was laid in 1861 followed by the start of construction in 1862. After numerous setbacks, construction was completed in 1874; it was interrupted by numerous incidents, including the Franco-Prussian War(普仏戦争), the fall of the Empire(帝政)and the Paris Commune. Another problem was the extremely marshy(湿地の)ground with underground water or an underground lake beneath the site, which caused continual pumping for eight months before the concrete foundation could be laid. This is said to have required the construction of an underground reservoir(貯水池)below the building; this "lake" later inspired The Phantom of the Opera's lair(ねぐら).