Ocean Floor
So far the info on the Ocean Floor is a bit limited. The evironment as well as the "people" living there has only been mentioned very little and mostly in Hatchan's side adventure. But even then it shows that there is an environment where not only sea creatures but also people, the fishmen are living in.
Since so little is known about the entire properties of the environment down there, as well as if there is borders between the serate Blues or between the Blues and the Grand Line etc. Because of that limited info we're listing the entire Ocean Floor as one place. Be it a location that is below the surface of the Grand Line or one beneath the surface of the Blues. If it gets mentioned within the story that there is clear differences between Grand Line Ocean Floor and East Blue Ocean Floor for instance at some point, then it will surely be mentioned here and the order will change. But until then the entire Ocean Floor remains as one place.
Places already visited by a Straw Hat Pirate: