User blog comment:Balbal1/End of the Grand line/@comment-244290-20160323004416

On that island is something that would allow a pirate crew to know about the history of the world. Maybe a Poneglyph that is detailed and straightforward about the Poneglyphs themselves. A 'first' one if one was reading them in the intended order.

I would not be surprised if there is a Marine presence on or near the island, but it would not be G-1 (that island is as close to Mariejois as Marineford is).

The fact that every log pose goes to it might just mean that it is the only island around, which matches the (representational) illustrations.