I only visited Hovgarden, which is located on the calm island of Adelsö. This can only be reached by a car ferry. The ferry runs every half hour all day, and even on a Saturday afternoon, I found it wasn't too busy. The ride is free, as well as the entrance to the archaeological site.

The Hovgarden part of this WHS comprises a few rune stones, burial mounds and the remains of a palace (only part of a wall is still visible). They lie in the center of Hovgarden town. It's a nice stroll through the fields, and information is posted along the way. From on top of the hill where the palace stood, there are good views on the surrounding lake and Björkö (for Birka).

The walk ends at the medieval Adelsö Church, a lovely small romanesque construction. Inside there are runic stones too, but unfortunately, I couldn't get in as a wedding service was going on. So after about an hour I ended my visit and took the ferry back.