The "City of Doors," also known as Sigil, is a central location in the Dungeons & Dragons multiverse, particularly in the Planescape campaign setting. It is famous for its numerous portals that connect to various planes of existence, allowing travelers to access different worlds. The city is ruled by the enigmatic Lady of Pain, who maintains order and prevents any gods from entering. Sigil is characterized by its unique architecture and diverse population, consisting of various races and creatures from across the multiverse. The city has no clear government or law, but its inhabitants navigate the complex social dynamics and factions that vie for power and influence.