Provincial Days in New Zealand
The Holidays Act 1981 specifies each locality observing a Provincial Anniversary Day to celebrate the founding days or landing days of the first colonists of the various colonial provinces.
However the exact dates are not legislated for.
The regions covered are set by provincial district (as they stood when abolished in 1876), plus Southland, the Chatham Islands, South Canterbury and Northland.
The actual observance days can vary even within each province and is due to local custom, convenience or the proximity of seasonal events or other holidays.
This may differ from the official observance day, and may be several weeks from the official day.