5. Great Blue Hole-Belize 洪都拉斯蓝洞
The Great Blue Hole is an underwater sinkhole off the coast of Belize. The hole is 1,000 feet across and 400 feet deep. It was formed as a limestone cave during the last iceage
洪都拉斯伯利兹市附近海域有一处叫做“蓝洞”的水下坑洞,这个大洞直径为1000英尺,深400英尺。它是在冰河时代末期形成的一个石灰石坑洞。