The Zwiefalter Aach or Zwiefalter Ach is a river in Reutlingen district and Biberach district in Baden-Württemberg, Germany.

It is approximately 9 kilometres long and is a tributary of the Danube near Zwiefalten.

The river is known for the Wimsener Höhle.

This article related to a river in Baden-Württemberg is a stub.

You can help Wikipedia by expanding it.