Introduction to Ni Weng Cave: Ni Weng Cave is located in the northernmost part of the "Three Apertures of Yanggu". The cave is two feet high and five feet wide. The cave has two entrances, one is from the northeast and the other is from the southeast. In the middle of the cave are three characters "Chu Yanggu" in regular script. "Xiandu Zhi" says: "The "Kuo Cang Xu Zhi" written by Chen Baipeng, a native of Jiatai County in the Song Dynasty, says: 'The cave belongs to Xiandu Mountain, next to Lian River. There are three characters of the name of the cave on the cliff in Chuyang Valley, or it means Li Yang Bingzhuan.' "The word "beginning" is missing. It can only be completed when the first ray of sunshine shines in the morning. The duration is extremely short and the opportunity is very rare.