Karstquelle Blautopf (HHV Laichingen)The Blautopf – a karst spring of infinite beauty. Its unique location in Blaubeuren's rocky valley basin has made it one of the most popular tourist attractions in the Swabian Alb. Designated a national "geotope" (a significant geological formation), the 21-m deep spring with its blue to turquoise-green colour continues to draw people under its spell.