Even at submarine depths, the oceans are poorly mapped. In 2005, the USS San Francisco collided with an uncharted (but suspected) seamount at 160m depth. [0] h

Even at submarine depths, the oceans are poorly mapped. In 2005, the USS San Francisco collided with an uncharted (but suspected) seamount at 160m depth. [0] https://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711)#Grounding_with_seamount https://en.wikipedia.org/wiki/USS_San_Francisco_(SSN-711)#Gr...