Ancient cities whose brick and stonewalls have literally been vitrified, that is-fused together, can be found in India, Ireland, Scotland, France, Turkey and other places.

• 古城的砖块和石墙都成了玻璃状，一起烧焦了，可以在印度、爱尔兰、苏格兰、法国、土耳其和其他地方找到。