The development of Lechaschau was mainly based on the construction of a bridge over the Lech River in 1464, on which salt was being transported from Reutte into the Tannheimertal over centuries. Close to the bridge the scattered village centre was built from which recent developments have been built radially. Lechaschau with its small commercial and industrial companies is the second largest village within the Reuttener Basin. However, the majority of its population has to commute to other villages. Till the mid-20thcentury Lechaschau and Wängle formed one parish. Today's parish church Heiliggeist was founded together with a hospital in 1522.