Reformation Day (31 October) is a Protestant holiday celebrating the onset of the Reformation. It is said that on this day in 1517, German monk Martin Luther nailed his famous Ninety-Five Theses to the door of the All Saints' Church in the town of Wittenberg ─ thereby instigating the spread of Protestantism in opposition to Roman-Catholicism. The holiday is celebrated by Protestant communities including the Evangelical-Lutheran church: the largest religious community in Hamburg.
Then marking the event's 500th anniversary, Reformation Day has been made an official public holiday in Hamburg from 2017 onwards. On 31 October, schools, shops, banks and offices therefore remain closed, leaving most employees free to enjoy a day off work ─ and children a day off school.
Those who'd like to religiously observe Reformation Day can join celebratory services at the various Protestant churches around Hamburg.
Not the religious type? Most years, you might spend the extra day off exploring Hamburg's green outdoors, the zoo or one of the city's many museums ─ or by dressing up as somebody's nightmare for a Halloween party. However, in 2020 you should limit your day-off activities to outdoor exploration and at home fun with those in your household.