- Number of holidays
- 16
- Day of the year
- 138
- Days left in the year
- 227
International Museum Day was established by the International Council of Museums in 1977 to highlight museums as institutions that preserve cultural heritage, advance research, and serve as spaces for community exchange — with a new theme chosen each year. Victoria Day is a Canadian federal public holiday observed on the last Monday before May 25, honoring Queen Victoria’s May 24, 1819 birthday and now also marking the reigning sovereign’s official birthday in Canada. Haitian Flag Day marks May 18, 1803, when Haitian revolutionary leaders tore the white stripe from the French tricolor and sewed the remaining blue and red together, creating the flag that symbolized their break from colonial rule. National HIV Vaccine Awareness Day was established to recognize the scientists working on HIV vaccine research and to raise public awareness of the ongoing need for a preventive vaccine. Museums, monarchs, a torn flag, and a vaccine still in the pipeline.
All Holidays On May 18
National No Dirty Dishes Day
Battle of Las Piedras
Haitian Flag Day
I Love Reese's Day
International Museum Day
Mother Whistler Day
National Cheese Soufflé Day
National Visit Your Relatives Day
State Flag of Turkmenistan Day
Supply Chain Professionals Day
Victoria Day
World AIDS Vaccine Day
About May 18
May 18 Q&As
What is the most popular holiday on May 18?
On May 18, International Museum Day is the most globally recognized cultural observance, established by ICOM in 1977. Victoria Day is a Canadian federal public holiday honoring Queen Victoria’s May 24, 1819 birthday, and Haitian Flag Day is a major national observance marking the 1803 revolutionary flag creation.
What countries celebrate holidays on May 18?
May 18 observances span Canada (Victoria Day), Haiti (Haitian Flag Day), Uruguay (Battle of Las Piedras), Turkmenistan (State Flag of Turkmenistan Day), and the U.S., which hosts National HIV Vaccine Awareness Day and I Love Reese’s Day. International Museum Day is observed globally in more than 150 countries.
What awareness days are on May 18?
May 18 includes National HIV Vaccine Awareness Day, established to mark Clinton’s 1997 HIV vaccine call, World AIDS Vaccine Day, and International Museum Day, established by ICOM in 1977 to highlight museums as heritage and community institutions.