Oscarsborg fortress sight from Veiseving battery

General of Oscarsborg fortress at south Kaholmen island and it's Main battery is on the photo. South. Kaholmen with parapet battery Veyzving. Small island Bergholmen, where the mine station is located station and many other installations is seen on the left. The Håøya big island is seen on the right, which, as I also know, at least 4 large concrete batteries are located. In short, a huge field for further research and explorations is available here, all I need is a properly funding of new expedition...