Introduction to the Song Dynasty Coal Mine Site: Shanxi is known as the "Sea of Coal", and the east and west mountains of Taiyuan are uplifted, so the coal fields that stretch in the mountains on the east and west sides of Taiyuan are mostly within 350 meters below the surface, and the burial conditions are relatively shallow. The mineralization conditions are superior and the mining value is extremely high. It was under such unique conditions that the Taipei Mountain Sliding World was formed and preserved, which was known as black gold and was once a rare treasure of the people of Ze and Shanxi.