bottomless hole, 無底洞

It appears as if the Pacific Ocean is being drained away down a giant bottomless hole on the Oregon coast
Thor's Well gigantic hole in Oregon appears to be draining the Pacific Ocean | Daily Mail Online
Read more: http://www.dailymail.co.uk/travel/travel_news/article-3813917/Pictured-incredible-gigantic-hole-appears-draining-water-Pacific-Ocean.html#ixzz4LoQjfnBb
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