Du kan (ibland) komma in och ut från Sigil.
Från Planeswalkerens handbok , sidan 32
A secluded, hard-to-reach world called Athas is notable for a couple of reasons. First, "hard-to-reach" isn't just hyperbole; portals leading here are rare in the extreme, and spells that allow interplanar travel fail more than half the time. Recently, the githyanki attempted to reopen one of the few permanent portals to this world from the Astral, but their efforts were thwarted by the natives - which says a good deal for the inhabitants' might. Also, while the priests here have interesting connections with the Inner Planes, they refer to a number of the Paraelemental Planes by different names - so don't be confused if the sods talk about places called the plane of Sun or Rain.
Det finns också en psionisk-driven Planar Gate i det boxade set äventyret City by Silt Sea . Detta är en artefakt.