Klee Passage
Klee Passage is a shallow channel of water which separates Knox Atoll from Mili Atoll in the Marshall Islands.
A submarine sand bank is located directly under the water channel. Due to this sand bank, the passage is not accessible to large sea vessels which could easily get embedded in the sand. The sand bank was originally above water forming a connection between the two atolls however, the erosion by the sea carved out this passage.