The Jagged Pass is a small area which leads down from the top of Mt. Chimney all the way to the base by Lavaridge Town. This area is typically only able to be traversed from the top, but you can climb up it if you have the Acro Bike. It has a few spots where wild Pokémon dwell and, in Pokémon Emerald, it contains the entrance to the Magma Hideout