How germa66 travelled from north blue to south blue I was watching whole cake island arc in anime and it showed Germa 66 snail like ship climbing over red line.
But as far as I know, only way to cross grand line is through reverse mountain which has sea water flowing
Am I missing something here ?
The grand line is indeed what splits the world in half along the horizontal axis but ultimately it's only a body of water, surrounded by more water. You theoretically could sail North/South across the grand line without incident but that would entail sailing across the calm belts where no winds blow and gigantic neptunians tear ships apart. The thing is, the calm belts have already been conquered, the marines learned to embed seastones in the hulls of their ships to ward off neptunians and propel ships without the use of wind which allows them to cross the calm belts at will.  Its hard to imagine the obscenely rich and technologically advanced Germa66 who can cross the red line in mecha boats don't also have access to seastone to cross the calm belts.