Iceland was settled from Norway in the 9th century. The settlers brought with them a tradition of a seven-day week. Placed so far from other inhabitancies, they had to create their own week-based calendar. They developed their own currency, based on available commodities, such as fish, which was discarded at the turn of the 20th century with the aid of arithmetic textbooks.
Observations of the solar cycle soon revealed errors in the calendar which was cleverly amended. The calendar was later adjusted to the Roman calendar. It remained in common use for secular purposes until the 19th century. Special occasions related to it are still celebrated. Both systems, the currency and the calendar, are embedded in the local language and
serve to link generations together in their scope of time, nature and valuables.