Porkuni (German: Borckholm) is a village in Tapa Parish, Lääne-Viru County, in northern Estonia.

In 1479, a castle was built on an island in the lake by the bishop of Tallinn Simon von der Borch.

Porkuni castle (German: Schloss Borkholm) was a four-sided structure surrounding a central courtyard, where a small church stood.

In 1870–1874, a new manor house was built at the site by the landowner at the time, Otto Ludwig von Rennenkampff.

Perhaps not surprisingly, it is built in a neo-Gothic style, with turrets and other details inspired by a romantic perception of the Middle Ages.