Gruner See, Styria: The Park That Turns Into a Lake in Summer

Grüner See, literally “Green Lake”, is a lake in Styria, Austria, near the town of Tragoss, located at the foot of the snow-capped Hochschwab mountains. During winter, the lake is only 1–2 meter deep and the surrounding area is used…

How To Make an Electricity-Free Refrigerator

Conventional refrigeration does an incredible job keeping food fresh. But that technology hasn’t helped desert dwellers without steady electricity. A more recent development in refrigeration—the Zeer pot-in-pot refrigerator—only requires water, sand, and a hot, dry climate to preserve produce through…