From A Wiki of Ice and Fire
The Bower was built as a vast timber castle, presumably in the Dawn Age, since it was said to be made entirely from weirwood.[N 1] At some point, the name of the castle was changed to Greenfield.
- The text states that certain houses trace their roots back to the "golden age of the First Men", a term that could be meant to cover the Dawn Age and the Age of Heroes together. However, it also states that the seat of House Greenfield is made "entirely of weirwood", which means it was probably built before the Pact, the event that marked the end of the Dawn Age and the beginning of the Age of Heroes.