The Oslofjord narrows here, and the town to know is Drøbak, about ten kilometres away on the eastern shore. It is a long way from the real Lysefjord in Rogaland, but it has its own claim to a place in history.
On the night of 8 to 9 April 1940, the German heavy cruiser Blücher led an invasion fleet up the Oslofjord towards the capital. At Oscarsborg, a small island fortress in the narrows, old guns and torpedoes sank her, and the delay gave the Norwegian king, government and gold reserves time to leave Oslo. That is why the little fortress is treated with reverence. The fortress is open to visitors in summer, reached by a short boat from Drøbak, and the wreck of the ship is still on the bottom.
Drøbak itself is a delight, with a few thousand inhabitants in a tight huddle of white wooden houses, narrow lanes and a small harbour. It has long marketed itself as the Christmas town, and a year-round Christmas shop runs there, which sounds kitsch but is charming in the right mood. Walk along the waterfront, have a waffle, and look out at the island fortress, which sits in the water like a stone ship.
For riding, the roads down the east side of the fjord are good, with moderate bends, wooded hills and views of the water. They are not demanding, but they are pleasant, particularly outside rush hour, and a ride along the old road through the little villages is better than the motorway. Speed cameras are plentiful. The area is popular with cyclists on weekends, so give them room.
Fuel is available in Drøbak and in Nesoddtangen, though the larger choice is in Ski or Asker. Cafes at Drøbak are good for lunch, and the evenings in summer are long and light.
Visit on a calm morning in June or September, when the fjord is a sheet of silver and the traffic is light, and look for the island at the narrowest point.