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The entrance to the Desert Ruins.
The Desert Ruins is a location in Hoenn in Route 111's desert. Players can find Regirock in the inner chamber at level 40; it will have the moves Rock Throw, Curse, Superpower and Ancientpower.
To get to Regirock, the Sealed Chamber's puzzle must be completed. After this has happened, the ruins can be entered. In Pokémon Ruby and Sapphire, once in the lobby area, at the braille inscription, players must go two steps right, then two steps down, and afterwards use Strength to open the door.
In Emerald, however, players must instead go two steps left, then two steps down, and afterwards use Rock Smash to open the door.