One component of economic growth involved stimulating foreign investment in the Mexican mining sector. Through tax waivers and other incentives, investment and growth were effectively realized. The desolate region of Baja California Sur benefited from the establishment of an economic zone with the founding of the town of Santa Rosalía and the commercial development of the El Boleo copper mine. This came about when Díaz granted a French mining company a 70-year tax waiver in return for its substantial investment in the project. In a similar fashion, the city of Guanajuato realized substantial foreign investment in local silver mining ventures. The city subsequently experienced a period of prosperity, symbolized by the construction of numerous landmark buildings, most notably, the magnificent Juárez Theatre.