Caxias do Sul (kəshēˈəsh dŏ sōl) [key], city (1991 pop. 290,925), Rio Grande do Sul state, S Brazil. It is an important metallurgical center and has the most extensive vineyards in Brazil. There is little agriculture because of the rough terrain. The city was founded in 1875. It is a rail terminus and the site of the Universidad de Caxias do Sul.