Sigil /ˈsɪɡᵻl/ is a fictional city and the center of the Planescape campaign setting for the Dungeons & Dragons fantasy role-playing game.
Sigil was originally created for Planescape as the setting's "home base." According to Steve Winter in 30 Years of Adventure: A Celebration of Dungeons & Dragons, "A movable base, like a vessel of some sort (or an artifact, which was the original idea for the means of traversing the planes) wouldn't do it. It had to be a place that characters could come home to when they needed to, and it had to be central to the nature of the setting." Sigil's fifteen factions were created because, "Vampire: The Masquerade was a particularly hot game at [the] time and one of the ideas in it that we really liked was the clans. Jim Ward wanted to be sure that players had something to identify with and to give them a sense of belonging in this alien venue [Sigil]."
Scott Haring, in his review of the Planescape Campaign Setting for Pyramid, described Sigil as "a strange city with doors to every plane and every reality, and inhabitants from all those planes and realities living together in (more or less) harmony." Trenton Webb of British RPG magazine Arcane calls the city "splendidly bizarre" and declares that "Sigil, The Lady of Pain's citadel, is an elegant gaming construct, yet it can often feel a little hollow", feeling that life in Sigil should be "a swirl of plots, factions and sedition that leaves players' heads spinning, wounds bleeding and experience points tally in overdrive".Trenton Webb reviewed Uncaged: Faces of Sigil for Arcane magazine, rating it a 9 out of 10 overall.