The Challenger Deep at the Marianna trench is the deepest point on earth measuring 10.91km.
People used to think our oceans were pretty flat underneath the water and did measurements with a plumb. So when surveyors came to this particular point at this subduction zone the line proved to be too short.
When tectonic plates collide incredible forces apply. This deforms Earth considerably, mountain ranges like the Himalayans and the Andes are formed. However, the inverse happens, when one plate subducts under another one, creating massive trenches.
In April 2012 director James Cameron started a journey to the deepest point on earth, the Challenger Deep.
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