Valhalla

Valhala is a island in the Indian ocean. It can not be tracked and it can not be found unless you have a special talisman that the valkaries have. In one episode Leo is kidnapped and is stuck in Valhala. Piper,Phoebe,and Paige track Leo down with Wyatt.The Valkaries know when there are intruders on the island because if you orb or anything else without using a Valkarie talisman it will alert the Valkaries.