Sandgem Town is a town found in Pokémon Diamond and Pearl. It is the second town you come to in the game, the first being Twinleaf Town. Sandgem Town has two houses, one of them being the character's other rival's house. It has the Pokémon Lab which is run by Professor Rowan, a Pokémon Center and a Poké Mart. This town will be very useful after you beat the Elite Four and get a National Dex. Once you get the National Dex you can go to the house directly below the Pokémon Center. This is Dawn/Lucas's house. Talk to their little sister and she will tell you where a Pokémon Swarm is.