The Vereins-Kirche, popularly nicknamed the Coffee Mill Church for its distinctive octagonal shape and central cupola, was built in 1847 by German immigrants of the Adelsverein colonization society as a genuinely multipurpose community building rather than a church in the modern single-use sense. In its original form the structure simultaneously served as house of worship for multiple Christian denominations that took turns holding services, as the settlement's first schoolhouse, as a meeting hall for town government and public gatherings, and even as a fortified refuge and lookout point during periods of tension with Native American groups on the frontier. This shared, rotating use reflected the practical needs of a small, resource-limited immigrant colony that could not yet afford separate buildings for each civic and religious function. The original building was demolished in the 1890s after it fell into disrepair, but a replica was reconstructed in 1935 on the town's central Marktplatz using the same octagonal form. Today that replica functions as the Vereins-Kirche Museum, operated by the Gillespie County Historical Society, housing exhibits and artifacts on Fredericksburg's German settlement history. It no longer serves religious, educational, or defensive purposes but instead functions as a small history museum and iconic visitor landmark at the heart of the town's market square.