Hidden gargoyle

Finding It
On Backwash (Halo 2 Multiplayer Map), go towards one of the extending blue bridges. Find a plant that looks like you can walk on it. Crouch jump onto it and walk up it. Turn around and you jump forward. Walk toward the wall and then jump to the other side of the bridge and you will see a gargoyle. You can jump onto the gargoyle, but its not solid so you will go through it.