Located where the Chomel and Grande Grille springs emerge naturally, on the site of the first spa establishments, the Hall of Springs (Hall des Sources) was built in 1903 by architects Charles Le Coeur and Lucien Woog.
The design was modelled on the German trinkhalle, the idea being to gather a spa establishment's main springs at a single, easily accessible site, thus making it easier for curists to take the waters, facilitating the work of the water givers, while also encouraging foreign visitors to socialise and meet others.
The hall's bright, open, airy cast-iron structure was created by Émile Robert, a wrought iron craftsman. He designed the elegant Art Nouveau-style railings and reproduced here the thistles decorating the promenade gallery.
In 1928, the hall underwent major refurbishments: the perimeter railings were replaced by glass windows to protect visitors from draughts; the gargoyles were removed to clear the central area, and the glass skylight was raised and fitted with diamond-shaped panes to limit the greenhouse effect. A subsequent modernisation campaign in the early 1970s led to the removal of the original drinking stands and the water givers.