GoodTime
Society, Holidays, Calendars and Lists - GoodTime. Calculates the date of Easter from the year 1 to the year 9999.
http://www.davidemonti.com/
Free Printable Calendar Templates
Society, Holidays, Calendars and Lists - PrintableCalendar.ca. Download free printable calendars for the year 2002 and up.
https://www.printablecalendar.ca/
Multicultural Calendar 2004
Society, Holidays, Calendars and Lists - Multicultural Calendar 2004. The theme of the 7th edition is The Magic of Music.
http://www.multiculturalcalendar.com/
INTERFAITH CALENDAR
The Interfaith Calendar: primary sacred dates for all worldreligions
https://www.interfaithcalendar.org/
world-calendar.com - A web-based perpetual calendar
Contains holidays of over 75 countries and holidays of four religions: Christian, Islamic, Jewish, and Orthodox. In addition, it includes four other calendrical systems, Chinese, Japanese, Hebrew, and Islamic, all of which are relative to Gregorian.
https://www.world-calendar.com/
Earth Calendar
Society, Holidays, Calendars and Lists - Earth Calendar. A global events calendar which documents the holidays and occasions from countries and religions around the world.
http://www.earthcalendar.net