The Ziller Valley is a valley in Tyrol, Austria that is drained by the Ziller River. It is the widest valley south of the Inn Valley and lends its name to the Zillertal Alps, the strongly glaciated section of the Alps in which it lies. The Tux Alps lie to its west, while the lower grass peaks of the Kitzbühel Alps are found to the east.

The Inn is a river in Switzerland, Austria and Germany. The 518 km (322 mi) long river is a right tributary of the Danube, being the third largest tributary of the Danube by discharge. The highest point of its drainage basin is the summit of Piz Bernina at 4,049 m (13,284 ft). The Engadine, the valley of the En, is the only Swiss valley whose waters end up in the Black Sea.