The Vils is a 36-kilometre-long (22 mi) river, a left tributary of the Lech in the Alps of Austria and Germany.

The Vils has a drainage basin of approximately 200 km2 (77 sq mi), with an average annual precipitation of nearly 2,000 mm (80 in).

From here the Vils descends down the waterfall Vilsfall, only slightly east/northeast of the Oberjoch Pass and only a few hundred metres east of the border to Germany.

Then the river crosses the border into southern Bavaria, turns northeast and reaches the municipality Pfronten in the district Ostallgäu.

With an average discharge of 76.8 cubic metres per second (2,710 cu ft/s), the Vils is among the largest rivers in Bavaria.