Flateyri is in Önundarfjörður and has been a trading post for over two centuries. Hans Ellefsen operated a whaling station there for 12 years until it burned down in 1901. After this occurred, he gave government minister Hannes Hafstein (1861-1922) his stately house at Sólbakki, which Hannes then had moved to Reykjavík. Today, it is situated on Tjarnargata by Tjörnin pond and is used for government meetings. An avalanche tragically fell on the town in late 1995. Defensive walls were then constructed, which tower over the town.

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