Special events and other funny days

Fandens fødselsdag is the name of the danish and norwegian dates june 11 and desember 11. In 1656 it was decided that these dates would be due for payment of interest and installments.
The first written mentioning of fandens fødselsdag is from 1888.

According to the folklore you would only get berggylt, fjesing and knurr if you went fishing on fandens fødselsdag.