The Ge'ez calendar has 13 months. It includes 12 months of 30 days each and an extra month called Pagumē with 5 or 6 days, depending on the year. The Ethiopian new year starts on Meskerem 1 ...

Lunisolar calendars, with fixed weekdays, existed in many ancient cultures, with certain holidays always falling on the same dates of the month and days of the week. The idea of a 13-month perennial ...