Introduction to Xijiao Scenic Area: Xiji Canyon stretches five miles from east to west. The rocks at the bottom of the valley are flat and gravel-free, ocher in color, and the stream flows like a long dragon swimming, so it is called "Dragon Street". Long Street meanders for several miles, with overlapping peaks and rocks on both sides. The upper reaches include Shimen Waterfall and Water Curtain Cave, and the lower reaches include Bazhe Waterfall and Longshan Lake. Tsinghua University's quiet and serene atmosphere is rare elsewhere. It is dizzying and can be called a natural painting screen.