San Juan del Rio:
San Juan del Río is a city and administrative seat of the surrounding San Juan del Río Municipality in the central Mexican state of Querétaro. The city and municipality both rank second in population in the state. It is located on the country's central plateau (altiplano), 50 km (31 mi) south-east of state capital Santiago de Querétaro, at 20°23′N 99°59′W and an elevation of 1,922 metres (6,306 ft). Famous for its opals, mined at nearby La Trinidad, it is also an agricultural center (corn, wheat, sugarcane, beans, alfalfa, fruit, and livestock) and has some light industry. A number of wineries are also located in the vicinity. It is connected to Santiago de Querétaro and Mexico City by the mainline freight railway and Federal Highway 57.
