🌿 Nature & Environment
International Mountain Day
Dec 11
International Mountain Day on December 11 highlights why mountains matter for water, climate, biodiversity and the people who live there.
December 11: National Days & Holidays
December 11 is International Mountain Day, plus 2 more. Here’s everything celebrated on this date.
3observances on this date
345thday of 2026 (out of 365)
20days left in 2026
🔬 Science & Technology
National App Day
Dec 11
National App Day on December 11 celebrates the mobile apps we use every day. Learn the history of app stores, fun facts…
🤝 Awareness & Causes
UNICEF Day
Dec 11
UNICEF Day on December 11 marks the founding of the UN children's agency in 1946. Learn UNICEF's history, its work today and…
December 11 at a glance
- What national days are on December 11, 2026?
- December 11, 2026 has 3 observances: International Mountain Day, National App Day and UNICEF Day.
- What day of the year is December 11?
- December 11 is the 345th day of 2026, out of 365 days.
- How many days are left in the year after December 11?
- There are 20 days left in 2026 after December 11.
- What day of the week is December 11, 2026?
- December 11, 2026 falls on a Friday.
More in December
December 2026
SunMonTueWedThuFriSat1World AIDS DayRosa Parks Day+12National Mutt DayNational Special Education Day+13International Day of Persons with DisabilitiesNational Roof Over Your Head Day+14National Cookie DayNational Sock Day+15International Volunteer DayWorld Soil Day+16St. Nicholas DayNational Miners Day+17National Pearl Harbor Remembrance DayNational Cotton Candy Day+18Feast of the Immaculate ConceptionBodhi Day+19National Pastry DayNational Llama Day+110Human Rights DayDewey Decimal System Day+111International Mountain DayNational App Day+112Feast of Our Lady of GuadalupeNational Gingerbread House Day+113St. Lucia DayNational Cocoa Day+114Monkey DayNational Bouillabaisse Day+115International Tea DayBill of Rights Day+116Las Posadas (begins)Boston Tea Party Day+117SaturnaliaNational Maple Syrup Day+118National Twin DayNational Ugly Christmas Sweater Day+219National Emo DayNational Hard Candy Day+120National Sangria DayInternational Human Solidarity Day+121Winter SolsticeYule+222Forefathers’ DayNational Short Girl Appreciation Day+123FestivusNational Pfeffernüsse Day+124Christmas EveFeast of the Seven Fishes+125Christmas DayNational Pumpkin Pie Day+126Kwanzaa (begins)Boxing Day+227National Fruitcake DayInternational Day of Epidemic Preparedness+128Holy Innocents’ DayPledge of Allegiance Day+129Tick Tock DayNational Pepper Pot Day+130National Bacon DayNational Bicarbonate of Soda Day+131New Year’s EveHogmanay+1