Demolished 1725 | ||
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Built Was known to exist as early as 1325 | ||
Onstaborg was a borg in the northeast Netherlands. It was located in Sauwerd, Groningen. The borg was founded in or before 1325 by the family Onsta (also known as Onseda, Onsitha or Onsatha). The Onsta family belonged to one of the oldest and most prominent families of the Ommelanden. The Onsta family also owned an Onstaborg in Wetsinge.
References
Onstaborg (Sauwerd) Wikipedia(Text) CC BY-SA