This is one of a vanishingly rare breed these days - a manned lighthouse station.  Lille Færder Fyr is situated on the small island of Tristein, the centre one of a group of three small islands on the south western side of the entrance to Oslofjord.  The sharply tapering tower is of cast iron construction, a material that, as far as I can tell, is relatively unusual in a tower of this height.  The sections of the tower were cast by the Norwegian firm of Bærums Verk and assembled on site.  Historically, this is an extremely important station retaining, as it does, not only most of the original buildings in a relatively original condition, but also still having its original 1st order Fresnel lens.  The original semaphore station is also still present, the only remaining building of that type in Norway. 

The image below shows a landscape view of the site with the Color Lines ferry Color Viking passing on her way from Sandefjord in Norway to Strømstad in Sweden.