Wildegg Castle Estate includes all lands and properties outside the castle walls. It comprises numerous buildings to this day including Gasthof Bären and an organic farm.

Wildegg Castle Estate has undergone many changes and conversions over the course of the centuries as a result of sales and purchases. In around1770 it achieved its maximum extent of approximately 120 hectares of cropland, meadows, vineyard and commercial premises. From the 18th century onwards the Effinger family sold off parts of the property.

Along with the Castle Estate, the Effinger family also held governing rights over the villages of Möriken and Holderbank - including taxation and lower-level legal jurisdiction. The family passed judgement on smaller-scale offences, appointed the priest and was allowed to open commercial enterprises such as inns and mills. Apart from the fishing rights, these governing rights were lost when the French invaded in 1798.

After 1912, the Swiss Confederation was able to buy back some of the properties sold by the Effinger family such as Gasthof Bären in Wildegg. Today the estate has a surface area of some 100 hectares and comprises 37 buildings, a vegetable and pleasure garden, an organic farm, grapevines, forestry and fishing rights.

In 2011, Wildegg Castle Estate was converted into a foundation of the same name. The foundation is responsible for administering the entire estate. Museum Aargau runs the museum and takes care of the gardens. The aim is to give visitors the opportunity to experience all the facets of a Baroque castle estate in situ.