They are deep and narrow cavities that are often found in the waters of some oceans, particularly in the Pacific. They are next to the edges of volcanic islands or on the sides of the continents. The water temperature is very low ( 0 - 2 ° ) and some measuring more than 11000 meters. Example the Challenger trench or Mariana.
* Only one "like" per meaning and day, the more "likes" the meaning will appear higher in the list
