This year's stamps in Norway Post's lighthouse series are devoted to Kavringen and Medfjordbaen in the Oslo Fjord. Both are unmanned lighthouses.
Kavringen Lighthouse was built in 1892 and is located on Sondre Kavringdyne, a group of skerries in the western seaward approach to the Port of Oslo. There had previously been two lighthouses in the Oslo harbour basin, Heggholmen and Dyna, situated in the old main sea lane. Towards the end of the 19th century, however, larger vessels began to prefer the western lane between Kavringen and Hovedoya, round Vippetangen and into Bjorvika. After DS Norge ran aground on the Kavringen skerries in 1890, there was a cry for better lighting in the western approach. The Kavringen lighthouse was completed and operational only two years later. Until 1956, when both lighthouses were automated and the job of lighthouse keeper became redundant, the lighthouse keeper on Dyna was also responsible for Kavringen. On 15 May (St. Hallvard's Day), as part of Oslo's millennium celebrations in 2000, a time capsule made of titanium was bolted to the inside of the lighthouse. The time capsule is designed like the lighthouse's lantern housing and it contains letters and greetings from the citizens of Oslo to people of the future. The capsule cannot be opened until the year 3000.
Medfjordbaen is a sunken rock in the middle of the Oslo Fjord, off Slangentangen in the county of Vestfold. Here the lighthouse was built and went into operation in 1876. Medfjordbaen Lighthouse is a familiar rounding mark in the annual Faerder Regatta, on the way to Asgardstrand and Horten.