The Castle can be visited
Penningby castle

In the municipality of Länna, approximately 70 kilometers north of Stockholm, stands Penningby Castle, a medieval structure. It is considered one of the best-preserved castles from the Vasa era.
History+
The first documented mention of Penningby Castle dates back to 1380. The earliest known owner was Tord Bonde, who at that time served as Burgrave of Raasepori and Margrave of Wiborg. In the late 15th century, the complex underwent a transformation into a fortress under Birgitta Tordsdotter Bonde, the daughter of Tord Karlsson (Bonde).
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 59.6816, 18.6726