The calendar used by the Hobbits of the Shire
divided the year into twelve months which,
unlike the irregular months of Roman and modern Europe,
were of equal length:
every month in the Hobbit year had exactly thirty days.
This totals only 360 days,
so the left-over five or six additional days in each year
were invested in a pair of festivals, one at each solstice.
The two days of Yule fell around the Winter solstice,
between December and January;
the first day of Yule was the last day of one year,
and the second day of Yule was the new-year’s day of the next.
Six months later the festival of Lithe ornamented the Summer solstice,
and lasted either three or four days:
the first day of Lithe began the festival, followed by Midyear’s Day itself,
followed in leap years by an “Overlithe”,
and then the festival ended on the second day of Lithe.