A Neoclassical pavilion where you can find a fountain with healing thermal water accessible to the public. Why not taste it?
Wikipedia https://fr.wikipedia.org/wiki/Elisenbrunnen
Official website http://www.aachen.de/en/ts/170_sehenswuerdigkeiten/elisenbrunnen/index.html
Address Friedrich-Wilhelm-Platz, 52062 Aachen, Germany
Coordinates 50°46'26.833" N 6°5'12.761" E