Hammerschmiede Pehn, Aggsbach, Historical hammer mill in Schönbühel-Aggsbach, Austria.

The Hammerschmiede Pehn is a historical blacksmith workshop in Schönbühel-Aggsbach powered by three separate water wheels that drive a hammer, bellows, and grinding stone. The building demonstrates how metal crafting work was organized and performed over generations in this Alpine valley.

The smithy arose in the 16th century as a tool forge of Aggsbach Charterhouse on the Wolfsteinbach stream. After the monastery was dissolved in 1782 it passed to the Wimmer family of boatmasters, and in 1842 to tenant Matthias Penn, whose descendants still own it. The last smith, Josef Pehn, died in 1956; his daughter Maria organised a major restoration around 2000, after which the museum opened.

The smithy takes its name from Matthias Penn, who leased it in 1842 and whose descendants still own it; the last smith was Josef Pehn, who died in 1956. Today it operates as a museum with forging demonstrations, guided tours and Schauschmieden that can be booked, and it also hosts social events. The three water wheels are fed by a fluder from a 2,500 m² pond below the monastery weir.

This site is best experienced with a guided tour, as the mechanical systems are difficult to understand without explanation. Advance arrangements work well for school groups and larger visitors, allowing for proper demonstrations and context.

The workshop kept its pre-electric drive: three overshot water wheels still power a tail hammer, a bellows and a grindstone, and the wheels were never replaced by a turbine. The largest wheel turns a massive tail hammer through a cam shaft; such hammers were the standard for over 500 years until the spring hammer replaced them in the 19th century. A roughly 100-year-old Ajax 2 spring hammer from the Schmidt steelworks in Vienna stands as the next generation, and all machines remain functional.