What is "kammweg"

The Kammweg ("Ridgeway") was a long-distance path opened in 1904 along the crest of the Elster Mountains, Ore Mountains, Bohemian Switzerland, Lusatian Mountains, Ještěd Mountains, Jizera and Giant Mountains, Śnieżnik Mountains and High Ash Mountains. This path was once the longest tourist trail in the German-speaking region of Europe. Since 2011 the ridgeway tradition has been continued with the Ore Mountains-Vogtland Ridgeway (Kammweg Erzgebirge–Vogtland), which runs on the German side of the border.