I Think its by the spring path which is right below veilstone city. you can use yoru map for that. In Turnback cave you can catch Giratina, and special for platinum when you catch giratina, you can enter the distortion world, which you can get the grisious orb, which makes giratina orgin form like in the movie "Giratina and the Sky Warrior"
turn back cave
turn back cave
I don't think Turnback Cave is assessable on diamond.
after you got the national pokedex there will be a new lake cooled turn back cave near route 214.
go to turn back cave
giratina is at the end of turn back cave
spring path, then turn back cave
you have to beat the elite 4 and go back to turn back cave where giritina is in Pokemon diamond or pearl. and its next to a portal. you have to beat the elite 4 and go back to turn back cave where giritina is in Pokemon diamond or pearl. and its next to a portal. you have to beat the elite 4 and go back to turn back cave where giritina is in Pokemon diamond or pearl. and its next to a portal.
he should be in turn back cave after you get the natinal pokedex =)
its the same in pearl. he's in turn back cave.
it will be. dont worry about it.
You go to route 213 and then go to spring path and then go in the cave that is there.