The McFarlane Foundry was the oldest machine shop and foundry in Colorado, a predecessor of the huge Hendrie and Bolthoff Mining Machinery Company. Its rubble-stone ruin was incorporated by the Central City Opera House Association into a rehearsal center. This $2 million, state-of-the-art center has a large performance hall, an elegant lounge, and recital and rehearsal rooms. The restoration was an especially challenging project for the architect, who had to underpin the foundry's native granite walls in order to incorporate them and had to contend with building over Eureka Gulch and its wooden flume. Rodney Davis sensitively incorporated ancient wooden doors and shutters as well as foundry tools and ruins. New and old corrugated and pressed metal helps blend old spaces into new ones in this exquisite, reborn building. Despite a few roof vents for height and light, the understated, one-story structure fades into the surrounding aspen forest.