Yakima Ridge is a long anticline in south-central Washington, running from north of Yakima east-southeast through the Yakima Training Center to Hanford Reach National Monument and the Hanford Site. It is one of several parallel ridges that organize this dry inland landscape, with nearby valleys and neighboring ridges helping define the region’s geography. As part of the Yakima Fold Belt, it was formed when Miocene Columbia River basalt flows were later folded, creating its long arched shape rather than a single peak. A notable feature is Selah Gap, where the Yakima River cuts directly through the ridge, illustrating a broader regional pattern of water gaps.