Ullerøy is a peninsula and urban area in the municipality of Sarpsborg in Østfold, Norway.
[1] Before 1992 Ullerøy was a part of Skjeberg municipality.
The first element is the genitive case of the name of the Norse god Ullr.
The former island was later turned into a peninsula because of post-glacial rebound.
This Østfold location article is a stub.