Plains fan out where the city of Buenos Aires ends: this is the beginning of the pampas, which derive their name from the native Quechua word for "flat field." All over this fertile earth are signs of active ranch life, from the grazing cattle to the modern-day gauchos. The region is also noted for its crops, although these days the traditional alfalfa, sunflowers, wheat, and corn have largely been replaced by soy.
While Argentina was still a Spanish colony, settlers gradually began to force indigenous tribes away from the pampas near Buenos Aires, making extensive agriculture and cattle breeding possible. (In 1880, during the bloody Campaign of the Desert, the southern pampas were also "cleared" of indigenous tribes.) By the latter half of the 19th century the region had become known as the grain supplier for the world. From 1850 to 1950 more than 400 important estancias were built in Buenos Aires Province alone. Some of these have been modified for use as guest ranches and provide the best glimpse of the fabled pampean lifestyle.