Caldwell Located in the heart of scenic southwestern Idaho, the greater Caldwell area is a desert brought to bloom by the wonders of irrigation. Caldwell is situated in the Treasure Valley along the Boise River. Covering an area of approximately 12.5 square miles, the city sits at an elevation of 2,428 feet above sea level. The valley is surrounded by the Owyhee, Weiser and Boise mountain ranges that rise steeply to 8-9,000 feet above sea level and range in distance from eight to twenty miles away from Caldwell, surrounding the Treasure Valley. The slopes are partly covered with sagebrush, which gives way to chaparral, then to ridges of fir, pine, spruce and juniper. Recreational activities are a highlight of Idaho and the Caldwell area provides access to a variety of enthusiasts from rock hounds to river rafters, skiers to hot springs lovers, trail riders to hikers and much, much more.