Spirit Plane

The Spirit Plane is a plane of existence from which Summoning energy can be used to summon creatures.

Very little is known of the Spirit Plane. According to the druid Pikkupstix, it is here that spirits freely wander. When some one summons a monster, one of these spirits manifests itself in Gielinor as that creature.

Whether or not the Spirit Plane is a separate world, or universe, from Gielinor is unknown. It may be another "part" of Gielinor, although it is not a geographic location on the planet.

Upon reaching 99 Summoning, when you talk to Pikkupstix, he mentions how this Plane has never been part of our world, but is in our lives every day. By this he is referring to a spiritual realm probably as another dimension or a realm that is connected, but not part of Gielinor.