Desert Resort is a gigantic desert in Black and White and Black 2 and White 2 at the northwest end of Route 4 filled with mysteries and the ruins of the Relic Castle. In Black and White, there are two entrances to Relic Castle along with five Darmanitan which, according to Professor Juniper, have been guarding the ruins in a meditative state for 2500 years. You may also catch one out of the five Darmanitan with the ability Zen Mode after awakening it with a Rage Candy Bar, which can be obtained from Professor Juniper.
In Black 2 and White 2, the leftmost entrance to Relic Castle has been buried in sand, leaving the other entrance the only exposed one in the Desert Resort. Another lower storey of Relic Castle consisting of five rooms can be accessed via the Relic Passage, where the Pokémon Volcarona can be caught in the central room. The Darmanitan outside the single entrance in the Desert Resort will also be gone.