The village is located between Olpe and Attendorn on the L 512 directly at the Biggetalsperre. Due to the railroad station directly at the lake with the home port of the "White Fleet" of the passenger shipping Biggesee, Sondern has the only lake railway station in North Rhine-Westphalia. The beautiful circular path around the Biggesee - whether on foot, by bike or on inline skates - offers pure relaxation.
At the Sonderner Kopf there is a lido with kiosk and adjacent camping site.