Yinshi Valley is a rocky mountainous area with tall pillars. It’s top areas have grass on them. The pillars make it difficult for planes to fly through the valley
On July 12, 2019, during the Lighthouse War, two squadrons were performing recon in the area around Yinshi Valley, and were chased down by MQ-99 UAVs into the valley. Spare Squadron entered the airspace, despite ongoing thunderstorms in the valley, and helped the squadrons escape.
- Yinshi's rock pillars are based on the Zhangjiajie National Forest Park in Hunan, China. This location was also used as the basis for the floating Hallelujah Mountains in the 2009 film, Avatar.