エーストフォールの洞窟・トップ4

The fortress, built between 1661 and 1701, was built to protect against Swedish attacks.

Halden is a pleasant town located right on the Iddefjord, close to the Swedish border. Its most prominent feature is the historic Fredriksten Fortress situated on a hill overlooking the town and water. In town, you can find nice streets and a harbourside area worth a stroll.

Fredrikstad was founded in 1567 by King Fredrik II. King Fredrik III commissioned the Dutch Quartermaster General Willem Coucheron to build a fortress to defend the city. Today it is Northern Europe's best-preserved fortress. Source: https://de.m.wikipedia.org/wiki/Fredrikstad

A visit is a must, discover this beautiful place, many photo opportunities

The fortified town of Fredrikstad was one of the most important strongholds between Bohus Fortress (Båhus, today Sweden) and Akerhus Castle (Oslo) in the Middle Ages. During the Hannibal feud (part of the 30-year war, also known as the Torstensson War), the city was expanded into a fortress city, initially with simple earth walls and moats. The fortress has been repeatedly rebuilt and expanded over the centuries and has been preserved to this day. The city is located on the east bank of the river and also serves to control the Glomma River. The outworks Isegran (1657), Cicignon (1677) and Kongsten (1682-85) were added later. Isegran and Cicignon lay on the west bank of the river. The Kongsten was built on a rock to the east of the city.

Unfortunately, the castle is not at the marked place, but almost 3 km further. (Best to look at Google Maps)

Frederikstad is a well-preserved former fortress town from the time of the great Nordic wars. Today it is a tranquil tourist destination. https://de.wikipedia.org/wiki/Fredrikstad

This fortress is hidden in the forest. Cannons and good view.