Utö

There are two graticules named Utö ("outer island" in Swedish):

As might have been expected with a name like that, both graticules are mostly water (Baltic Sea), with some islands near the (northern) edge.

According to the corresponding Wikipedia disambiguation page, those two appear to be the only places named Utö, though there is a town named Uto (no umlaut) in the Kumamoto, Japan graticule.