KnowraAlexander horned sphereLinked fromLinked fromThe 6 pages that link to Alexander horned sphere, each with the reason it gives.All 6Broader topic 2Related 1Compared with 3Algebraic topologyBroader topic: It shows that abstractly simple spaces can behave unexpectedly when embedded in other spaces.Schoenflies problemBroader topic: Its inside is not a ball, giving a canonical negative example for unrestricted embeddings.