HIDALGO, an inland state of Mexico, bounded N. by San Luis Potosi and Vera Cruz, E. by Vera Cruz and Puebla, S. by Tlaxcala and Mexico (state), and W. by Queretaro. Pop. (1895) 551,817, (1900) 605,051. Area, 8917 sq. m. The northern and eastern parts are elevated and mountainous, culminating in the Cerro de Navajas (10,528 ft.). A considerable area of this region on the eastern side of the state is arid and semi-barren, being part of the elevated tableland of Apam where the _maguey_ (American aloe) has been grown for centuries. The southern and western parts of the state consist of rolling plains, in the midst of which is the large lake of Metztitlan. Hidalgo produces cereals in the more elevated districts, sugar, maguey, coffee, beans, cotton and tobacco. Maguey is cultivated for the production of _pulque_, the national drink. The chief industry, however, is mining, the mineral districts of Pachuca, El Chico, Real del Monte, San Jose del Oro, and Zimapan being among the richest in Mexico. The mineral products include silver, gold, mercury, copper, iron, lead, zinc, antimony, manganese and plumbago. Coal, marble and opals are also found. Railway facilities are afforded by a branch of the Vera Cruz and Mexico line, which runs from Ometusco to Pachuca, the capital of the state, and by the Mexican Central. Among the principal towns are Tulancingo (pop. 9037), a rich mining centre 24 m. E. of Pachuca, Ixmiquilpan (about 9000) with silver mines 80 m. N. by W. of the Federal Capital, and Actopan (2666), the chief town of the district N.N.W. of Pachuca, inhabited principally by Indians of the Othomies nation. HIDALGO (a Spanish word, contracted from _hijo d'algo_ or _hijo de algo_, son of something, or somewhat), originally a Spanish title of the lower nobility; the hidalgo being the lowest grade of nobility which was entitled to use the prefix "don." The term is now used generally to denote one of gentle birth. The Portuguese _fidalgo_ has a similar history and meaning.