Naltoros designated P3X-637 was a planet in the Milky Way galaxy which held a Stargate. The planet is an off-world colony for five hundred surviving Altairans. Naltoros is not the idyllic paradise that Altair itself once was. The world is dry with very little water, and covered with hard stone. The survivors chose this world because of its natural resources.

They built a city on the planet and some factories and then a defense shield above the city as a protection against Goa'uld. (RPG: "Fantastic Frontiers: Stargate Season One")