Karlsøya is an island in the municipality of Sarpsborg, in Østfold county, Norway. Before 1992, Karlsøya was a part of Skjeberg municipality. The island's only connection with the mainland is a bridge that connects the island with the peninsula of Ullerøy.
![](http://upload.wikimedia.org/wikipedia/commons/thumb/6/6b/Karls%C3%B8ybrua.jpg/220px-Karls%C3%B8ybrua.jpg)
59°08′47″N 11°08′22″E / 59.1463°N 11.1394°E