The construction of the Grand Palais was an architectural feat that took barely three years. From the outset, however, work was delayed by the unstable subsoil near the Seine, which forced the building to be built on piles. The workers drove 3,400 wooden piles 10 metres long into the clay soil. The steam hammers shook the whole neighbourhood. The structural steel elements were manufactured in the factory and brought in by barge. Exactly 9,057 tonnes of steel and 200,000 rivets were needed. The result was a triumph, and on 14 April 1900, the World Fair was inaugurated by the President of the Republic, Emile Loubet.