Picturesquely situated in a high valley of the Hohe Tauern mountain range, it is known for the Gastein waterfall and a variety of grand hotel buildings.Radon inhalation therapy at the Gasteiner Heilstollen began as a result of further investigation into the experiences of humans who worked in silver mining who noticed improvements in symptoms from various ailments.[citation needed] The Grandhotel Gasteinerhof has residential outbuildings and modern urban design integrates the historic ensemble, which includes a spa with a glass corridor over a creek with pristine alpine water.[5] The remote valley was settled by Bavarian peasants in the 9th century; field names in the highest-lying southern parts also denote a Carantanian (Slavic) colonization.It was originally an alpine farming and gold mining area and the site of an ancient trade route crossing the main ridge of the Central Eastern Alps.Already about 1230, the minnesinger Neidhart von Reuental had referred to the hot springs in his Middle High German poem Die Graserin in der Gastein.Since 2007, the town also annually hosts the Gastein Ladies tennis tournament, an International event on the WTA Tour, attracting top players like Julia Görges.