The Waldbahn railway line near Welzheim is one of the most beautiful railway lines in South Germany and listed as a monument. Its viaducts, however, require restoration. The 100-year-old Laufenmühle viaduct, for instance, exhibits major damage, such as cracks in the reinforced concrete. If the viaduct was restored with standard state-of-the-art methods, the expenditure and costs would be enormous and the monument character would be endangered. New work has now succeeded in bringing together the right partners and in developing a customized approach to sustainable repair of the viaduct.