Use in Denmark
The notion of "Tre Kroner", Three Crowns, is well known in Denmark since, in the 17th, 18th and 19th centuries when naval vessels were often named after heraldic devices, the navy usually had a ship of this name. From here it passed to the naval fort of Trekroner guarding the harbour of Copenhagen. It was also a common name for farms, causing a new city quarter in Roskilde to have taken over the name "Trekroner" from one such.
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