Where to get rock climb on Pokemon Platinum?

It's found on the route to Snowpoint City from Mount Coronet. About halfway to Snowpoint City, there is a small cabin with a hiker in it who says he lost his HM rock climb. Guess he's not very good at looking, because the HM is right behind the house next to a tree, you can't miss it. After you get it, talk to the man inside the cabin. Don't worry, he won't take it. In fact, since you already have something of his, you get another! He gives you an Icicle Plate for no apparent reason. The Icicle Plate, when held by a Pokemon, powers up Ice-type moves.