The Lac de Warfaaz is a small artificial lake about two kilometres from the town centre, created in the 19th century as part of the resort improvements. The shores are lined with horse chestnut trees and there is a paved promenade popular with walkers and cyclists. A small cluster of restaurants and cafes on the south shore makes it a pleasant stop.
In summer you can hire pedalos. The lake is not spectacular, but it provides a counterpoint to the thermal bustle of the town — quieter, surrounded by forested hills, and a good starting point for walks into the Ardennes countryside. The signposted walking routes from Warfaaz cover some of the better Ardennes scenery near Spa.