A deep blue lake, which by the way also inspired Eduard Mörike to his "Stuttgart Hutzelmännlein" - written in Swabian dialect with a tongue twister: "S'leit a Klötzle lead same with Blaubeura, same with Blaubeura leit a Klötzle lead."
In it he also tells of the beautiful Lau, a cross between a woman and a water nix who was banished by her husband in the blue pot, because she could not laugh and gave him only dead children.
The blue pot is the second most water-rich karst spring in Germany after the Aachtopf.
The blue color is caused by the light scattering on the smallest lime particles in the water. Due to the small size of the particles in the nanometer range, the blue light is preferably scattered.
The blue pot is followed by a large, mostly underwater cave system, which is explored by divers. In 2006, a 170 x 50 x 50m dry cave was discovered.
The blue pot in Blaubeuren in Baden-Württemberg is the second-richest karst spring in Germany. This is where the blue springs, which after about 22 kilometers in the city of Ulm flows into the Danube.
Known is the blue pot for the depending on the light more or less intense, but always striking blue color of its water. The blue color is caused by a physical effect of light scattering (so-called Rayleigh scattering) on the nanoscale lime particles that are dispersed in the water. Due to their small size, the blue light is preferably scattered and produces the blue glow. The same effect can be observed with the Blue Lagoon in Iceland; There, the effect is caused by nanoscale silicate particles.