With over a 120-year history of mining, the West Pit in Fushun City of northeastern China's Liaoning Province was the largest open-pit coal mine in Asia. And now it has luxuriant plants with dense foliage and charming flowers. In the abandoned mine pit, tree planters, who used to be miners, have been building a solid green zone with more than a million trees. Follow CGTN to witness the incredible transformation of this coal sea.