The Sauerquelle source lies on the steep slopes of Church's local mountain, Brambrüesch. It is accessible from the Brambrüesch mountain station or from Känzeli station on narrow and partially exposed paths. In 1994, forest group Chor-Obertor made the path to the source accessible again and the fountain was refurbished. The slope has been dyed red over the years by mineral water coming to the surface after flowing through mineral-rich stone for a long time. The red colour gives away the location of the little fountain. The "book of the spring" lets you look up who has recently drunk from the water.