Santa Rosalia is one of Baja's stranger small towns: a copper port built by a French mining company, pressed between desert hills and the Gulf of California. It is not pretty in the polished resort sense. Its charm is in the iron church, the old company buildings, the locomotives and mining gear still sitting around town, and the black volcanic sand along the water.
The Compagnie du Boleo founded the town in 1884 and left a layout and architectural mood that feels different from the rest of the peninsula. The best place to start is Iglesia de Santa Barbara, the prefabricated metal church associated with Gustave Eiffel. From there, climb into Mesa Francia for Museo El Boleo, housed in the former company offices, and wander the surrounding streets where old mining machinery still gives the place its rough industrial edge.
Santa Rosalia also works as a pause on the long Transpeninsular Highway. The town is compact, seafood is easy to find, and the old bakeries are famous around Baja for pan de El Boleo, a legacy of the French company-town years. Give it a few hours if you are passing through; give it a day if you like places where history still looks dusty and practical.