CASA Grande, a town of Mexico, in the province of Sonora, situated on the Rio Gila. Here there is still in existence an immense edifice, supposed to have been reared by the ancient Mexicans. It consists of three floors, with a terrace above them. There is no entrance to the under floor; and hence, access being only obtained by means of a scaling ladder, it is supposed that the building was designed for a fortress. Long. 113. 23. E. Lat. 33. 40. N.