Situated on the cottonwood-banked bend of the Rio Grande, Alamosa is the transportation and trading center for the San Luis Valley. The valley - a high, flat semi-arid plain about 50 miles wide and 125 miles long - was once the bed of an ancient lake. Irrigated by the Rio Grande and artesian wells, it is one of the most productive farming areas in the state. Red McClure potatoes, lettuce and barley are among crops shipped from Alamosa. Alamosa is located southwest of Pueblo
, on Hwy 160/285. It is the closest major town to the Great Sand Dunes National Monument
. La Jara Reservoir and La Jara State Fishing Area are nearby.