The mountains are magnificent. With towering old trees, lush green grass and elegant wind shadow, the mountain is an ideal tourist destination. The highest peak, commonly known as the "Nantianmen", is 388.3 meters above sea level. When you reach the top, you can see the whole view of Jiangcheng. There is a site of an ancient city in the Bohai period on the mountain, but there are mountain city walls, "water dungeons" and "drought prisons". The city wall is built by rammed earth and gravel along the ridge, with the highest point 10 m and the lowest point 1 m. The wall width is 1 to 2m, and the base width is about10m. The circumference is 2396 meters. There is a gate in the north and south of the mountain city, and watchtowers in all directions. "Water dungeon", also known as "Longtan", is located at the lowest point in the northwest corner of the mountain city. It is rectangular, 22.8 meters long from east to west, 125.75 meters wide from north to south and more than 9 meters deep. It is surrounded by granite. The "water dungeon" was the reservoir of the mountain city at that time. The "drought prison" is located in a high place in the southwest corner of the mountain city, which is in a right circle. The "drought prison" has a diameter of10.6m and a depth of about 3m. Is it a warehouse for storing materials or a prison for holding prisoners in the mountain city? Kannonji, Longwang Temple and Guandi Temple, which were built in Qing Dynasty, are collectively called Longfeng Temple. In the 19th year of Qianlong (AD 1754), on the ninth day of August, the pure emperor Aisingiorro Hongli visited Longfeng Temple to offer sacrifices to Longtan, and inscribed a plaque for the main hall of Kannonji, naming a tall, straight and tidy Huang Po Luo tree as a "holy tree". Since then, every spring and autumn, officials of the Qing Dynasty stationed in Kyrgyzstan, headed by Jilin General, have come to Longtan Mountain to offer sacrifices to Longtan and Shenshu. During the Republic of China, the "holy tree" withered and withered. There are ancient city ruins, Shuidi Palace and Dryland Palace built in the 4th-5th century AD, as well as ancient buildings such as Longfeng Temple, Longwang Temple and Guandi Temple built in the Qing Dynasty. It is a provincial cultural relics protection unit. Longtan Mountain is one of the four famous mountains in Jilin City. Longtan Mountain Park, built on the mountain, is the largest urban scenic park in Jilin City and one of the urban forest parks with good natural ecological protection in China, which has high protection, utilization and development value.