Recurrence pattern: every year on December 4.

Miners' Day, or Barbórka, is observed in Poland every December 4, coinciding with the feast day of Saint Barbara, the patron saint of miners and those who work with explosives. The celebration has its roots in the legend of Saint Barbara, who was tortured and beheaded by her father for converting to Christianity. In Poland, this day has been informally recognized as Miners' Day for decades and is also regarded as a professional holiday for geologists and specialists in the fossil fuel industry. The festivities include special church services, marching band performances, concerts, balls, and various other activities. Additionally, Saint Barbara's Day is celebrated by some mining institutions in other countries, as well as by artillery units in several armed forces worldwide.