Oslo Fjord Islands is an editorial reference work. It exists because the Norwegian Mapping Authority holds a name for 1,230 islands, islets and skerries in this fjord, while hardly any of them are written up anywhere.

Where the numbers come from

Place names, place IDs and coordinates come from the Norwegian Mapping Authority’s central place-name register. The distance given for each island is a straight line from Rådhusbrygge 4, where the island boats leave, worked out with the great-circle formula. It says nothing about how long the journey itself takes.

Departure times are fetched live from Entur, the national journey-planner dataset, when you open an island page with a quay of its own. 20 of the islands have one. Departures marked «live» carry the vessel’s actual position; «scheduled» is the planned time. Seasonal services vanish outside the season, and then nothing is shown; Ruter’s timetable settles it.

Photographs come from Wikimedia Commons and are credited with photographer and licence on each page. 114 of 125 islands have one.

How the articles were made

Every article is written from stated sources and lists them at the foot of the page. 125 of the islands carry a source list. Where a claim rests on a single source, that source is named. Historical detail has been checked against Wikipedia and lokalhistoriewiki where both cover it.

Protection status is reported from the sources, but boundaries move and new decisions are made. Naturbase at the Norwegian Environment Agency settles it, and it is worth checking before you go ashore outside the prepared sites.

The two languages

The Norwegian text came first and is the source. The English is an adaptation rather than a translation: place names stay Norwegian, distances stay in kilometres, and Norwegian institutions and legal terms are explained once in English where they first appear. Numbers, dates and protection status are identical in both versions, and a build check compares them so a figure cannot drift in one language without failing in the other. Nothing here is machine-translated. You can read the same page in Norwegian.

The map

The coastline comes from OpenStreetMap and has been simplified so that it will load in a browser: 6,340 segments holding 363,000 points between them are reduced to 1,496 lines with the Douglas-Peucker algorithm. That keeps the shape of the fjord right, but not to navigational accuracy. The map here must not be used for navigation. Use official nautical charts. Map data © OpenStreetMap contributors.

Errors and gaps

Pages without an article still hold register data: name, municipality, coordinates, access and protection. There are 1,105 of those. If you find something wrong, it is worth saying so. A reference work is only as good as the corrections it takes in.