Where is...

[Pumpkin]

Battleship Island???

I cant find it, am I missing something here? Apparently there are some strong monsters there so I was looking for it, without success.

[Arumat]

"Battleship Island"?

Do you mean the airstrip with Bahamut? Or the "Island Closest to Heaven" / "Island Closest to Hell" .. Islands?

[Pumpkin]

I dunno

I read a Bestiary and under locations, some of them are listed under Battleship Island

[Jessweeee♪]

Battleship Island is in the middle of the ocean, in the lower left corner of the map. You'll need the Ragnarok. It's not marked, by the way. This is where you find Bahamut and Ultima Weapon. You'll have to defeat Bahamut to get to most of the monsters.

[Jiro]

Just cruise around that lower left corner, it's pretty easy to spot once you get close.

[Evol]

It's in the corner of the world.
You need Ragnarok to enter it.