See the related link. This is where I went if I ever had trouble with the game. It explained everywhere.
It's in the Ice Path.
Use the move whirlpool. If you have a feraligator teach it whirlpool.
whirlpool is not classified as a HM in that Pokemon series, only in heartgold/soulsilver is it a HM, in diamond it is only a simple TM (1use)
Well, if you have a Pokemon that knows whirlpool, you can go back to route 41 and go to the mysterious Whirlpool islands.
you need the HM whirlpool (whitch you get it at mahogany town when you shut down the machines lance will give you it)
SORRY DUDE THERis no hm for whirlpool in pokemon pearl diamond or platinum only heartgold and soulsilver. but that wuld be AWESOME:))
You go up to the Whirl and use the move Whirlpool and u and your Pokemon crosses it.
First you must have a badge from the Mahogany Town gym leader (he uses ice types). Next you must find the HM Whirlpool. Equip Whirlpool to a Pokemon and go to one of the Whirl Islands and use the move Whirlpool on a whirlpool.
You need to beat all 16 gym leaders then go to the whirlpool islands
Whirl Islands only exist in Gold, Silver, Crystal, HeartGold and SoulSilver.
know that place to get past the whirlpools? whirlpool island go into it and wander around i don't know the way but lugia is found in whirlpool island hope this helps!
In the cave behind the final gym there is a whirlpool, go beyond that and there will be another whirlpool, then there will be an exit leading to a grassy area and in there you can find charmander and charmelion (25% chance) then you can evolve it into charizard.