There is a little castle in the Dutch city Zeist, known as Slot Zeist (Castle Zeist). It looks more like a manor, actually, but it does have a moat. Originally built in the late middle ages, it was largely rebuilt between 1677 and 1686, by Dutch architect Jacobus Roman (1640-1716).
In the 18th century, the castle and surrounding estate became the center of the Moravian Church in Holland, when the landlord invited a group of Herrnhuter Brüdergemeine to settle on the estate. Their church and cemetery are still in use.
The current owner of the castle is the municipality of Zeist. It is used for exhibitions, and available for congresses, conferences, receptions or weddings. See their website for details.