This is one of the most famous castles with a moat in the region. 
You can almost feel, smell and experience the history that has passed over domain once controlled and owned by the castle Lords. 
Old trees provide shade and the moat is filled with fish. 

Split into two islands, the castle mirrors itself in colors ranging from deep greens to emerald tones. The park surrounding the site has a beautiful path with views from all sides of the walls and buildings.

Compared to other castles in Europe it's not very big, but this makes it all the more charming. The castle museum has been carefully restored and the views from inside over looking the grounds are beautiful. If you're looking for a place to discover a little more about Switzerland's past, than this is the right castle to visit. My suggestion is to visit on weekdays if you can, so that can have the place all to yourself.

Short history

The first mention of the castle is in the year 1256. However, the originally free noble family of Hallwyl were first mentioned in a testament from 1167. Some discoveries indicate that the castle was founded in the late 12th century. Hallwyl Castle was the home castle of the Lords of Hallwyl, who owned the surrounding land and parts of the lake as their personal property. It consisted of a residential tower with a dry moat. In 1265 the keep was expanded. In the early 14th century the dry ditch was converted into a moat. The old castle tower was surrounded by a moat and a wall on what became the Rear Island. To the east of the Rear Island, an artificial island was built in the River Aabach. This island, the Front Island, was outfitted with a curtain wall, and was occupied by residential and commercial buildings. During the conquest of Aargau in 1415 by the Swiss Confederation, the castle (which was known after 1369 as the Ganerbenburg) was burnt by the Bernese troops. The castle was immediately rebuilt and expanded. After the construction of two turrets in 1500 and 1579-1590 there was an extensive general renovation.