Exploring the history and evolution of Advent calendars NPRIn which period was the schedule devised?
At what time was the calendar first established?
In which period was the timetable arise?
When was the timetable originally created?
In which period was the timetable originally conceived?
At what time did the calendar firstly devised?
During what period was the schedule inception?
In what period did the schedule emerge for the first time?
