Broborg is one of Uppland's most magnificent ancient strongholds, strategically placed on a ridge along the former seaway, the "highway" of its day, that led Vikings to Old Uppsala and the Baltic Sea. The castle was built on a high hill, about 40 m above sea level. The castle was used between 6th and 11th centuries.
The castle had an outer and inner wall. The outer wall protected the longest sides to the south and east.The inner wall is almost completely enclosed and has a circumference of about 200 m. There were entrances in the southeast and west.
The visible walls of the stronghold tell its history and the many sagas associated with the site capture our imagination. One such saga is about Grimsa, the daughter of a powerful Viking chieftain who lies buried in a mound near the stronghold.
References:The first written record of church in Danmark locality date back to the year 1291. Close to the church are several stones with a Christian text and cross inscribed. The oldest parts of the present red-brick church are from the 1300s. In the late 1400s the church was enlarged to the appearance it has today. The church has been modified both internally and externally several times, among other things after the fires in 1699 and 1889. There are lot of well-preserved mural paintings in the walls.