The Palacio del Obispado (Bishop's Palace) is one of the oldest buildings in Monterrey and one of its most dramatic, perched on a hill to the west of the city centre with sweeping views over the entire metropolitan area. Construction began in 1787 but was never fully completed; it has served variously as a bishop's residence, a military fortress, a customs house, and a hospital before its current incarnation as a regional history museum.
The building is a handsome piece of late colonial architecture — thick stone walls, an interior courtyard, and a bell tower from which you can see clear to the Sierra Madre on a clear day. The museum inside covers Monterrey's history from the colonial period through the Revolution. The hill itself is worth the climb for the views alone.