Introduction to the stone carving with the character "ao": The stone carving with the character "ao" is one of the largest Chinese character carvings in the world today, with a height of 15 meters and a width of 8 meters. At that time, Mr. Yang Xuanting, a famous Chinese calligrapher, visited Yishan when he was 72 years old. He was intoxicated by the natural scenery of Yishan and happily inscribed this "AO" as a permanent memorial.