Yes, that's right. A sliver of land circles the world vertically - that's the Red Line - and the most dangerous linear stretch of ocean circles the world horizontally. That is the Grand Line. [Perona waves one finger in a circle, to stress her point.] Other than that, in the four blues...islands dust the waters all over.

I was born on the Grand Line itself, but I can't recall the type of island, or the name. [Or much of anything about her youth, actually. Perona mostly remembers being on Moria's ship most of her life.] Though for a decade I sails the seas as a key player to a great Pirate Warlord - living on the greatest and largest ship on my planet.