The history of ROCKWOOL goes back to the start of the 20th century, when the unique qualities of rock wool were discovered on the volcanic island of Hawaii. Scientists discovered a wool-like material in the trees around the active volcano Kilauea: rock wool in its pure, natural form. The material turned out to possess exceptional fire-retardant and insulating properties. In 1937, Gustav Kähler brought the volcanic material to Denmark and founded his first stonewool factory close to Copenhagen. In this factory, the natural process of the volcanic eruption was simulated. Still today, in our own rock wool factories, the natural process of volcanic eruption continues to be simulated.