The chronostratigraphic term Jurassic is directly linked to the Jura Mountains, a mountain range mainly following the course of the France-Switzerland border. During a tour of the region in 1795, Alexander von Humboldt recognized the mainly limestone dominated mountain range of the Jura Mountains as a separate formation that had not been included in the established stratigraphic system defined by Abraham Gottlob Werner, and he named it Jura-Kalkstein ('Jura limestone') in 1799.