Introduction to the Great Wall Ruins: The ancient Great Wall at Jiufeng Mountain was built in the Northern and Southern Dynasties and the Northern Wei Dynasty, and was rebuilt during the Wanli Period of the Ming Dynasty. Although it was a battleground for military strategists, the height of the city was less than one foot, and the width of the city was only three feet. Ups and downs, simple and desolate, are the most unique features of the Great Wall. To this day, the watchtower and beacon tower are still relatively intact. Climbing the enemy tower and looking into the distance, you will see the towering mountains, and the Bohai Sea and the sky in the distance, which are vast and majestic.