December 11 holidays, events, historyCategory: Короткие факты 0December 11 holidays, events, history 👉 HOLIDAYS: 🇺🇳 International Mountain Day. 🌏 UNICEF Birthday. 🌏 International Tango Dance Day. 🔹 NATIONAL HOLIDAYS: 🇧🇷 Brazil – Engineers’ Day. 🇺🇸