The longest cave in the world is the 'Mammoth Cave System' in the USA at 560,000 mtrs deep!
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Israel's Dead Sea is 1,312 feet below sea level.
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The city of Houston, Texas is built on a swamp and is slowly sinking!
89
The water between India and Sri Lanka is only 3-30 feet deep and was purportedly passable on foot until 1480 AD when a cyclone moved some sand around.
1
The Sahara desert expands at about 1km per month.
90
The state with the longest coastline in the Continental U.S. is Michigan.
31
The warmest temperature ever recorded on Antarctica was 3 degrees F.
175
A waterfall known as The Devil's Kettle empties water into a hole and nobody knows where it ends up!
18