科学家最近对号称世界四大圣地之一的美国蛇形大坟丘进行了放射性碳研究,以探明其建造的时间,建造人,以及为什么要堆造这个人工建筑。眼下每年都有2万余名游客从世界各地来到美国亚当斯的北部地区,就为了亲眼目睹这一世界奇迹。这个大型蛇形坟丘(Great Serpent Mound)堪称世界上最大的一座史前人工建造的丘形建筑物,因为它不知是什么时 Scientists recently conducted a radiocarbon study of the U.S. serpentine large tomb, one of the four holy places in the world, to find out when it was built, to build it, and why it was piled. Every year now more than 20,000 tourists from all over the world come to Adams in the northern part of the United States, just to witness the miracle of this world. The Great Serpent Mound is the largest mound of prehistoric man-made structures in the world because it does not know what it is