The landscape from the west side to the east side of Idaho's AVA changes quite noticeably. The eastern region's rough rocky terrain is a reminder of a once tumultous volcanic period. Canyons and an abundance of lava rock give the terrain a more striking appearance, from the rolling sandy hills of the western AVA region. Appearance is not what is important when it comes to choosing an area to plant vines, soil composition, however, is crucial. Lava rock produces Basalt soil, rich in Calcium, Iron, and Magnesium, all minerals vital to the health of the vine. Winemakers in this region know and take full advantage of this fertile, volcanic soil.