Pi Day is an unofficial holiday commemorating the mathematical constant π (pi). Pi Day is celebrated on March 14 (or 3/14 in month/day date format), since 3, 1 and 4 are the three most significant digits of π in the decimal form. In 2009, the United States House of Representatives supported the designation of Pi Day.^[2]

Pi Approximation Day is held on July 22 (or 22/7 in day/month date format), since the fraction ²²⁄₇ is a common approximation of π.^[3]

In the province of Quebec, Canada, the Construction Holiday is the most popular time for summer vacations.

In 1970, Quebec legislated an annual holiday for the construction industry which begins the 2nd last Sunday of July every year lasting for a period of 2 weeks, and the holiday came into effect officially in the summer of 1971. Many Quebecers outside the construction industry also take their holidays during these two weeks, and it is the busiest time of year for the province's tourism industry, with a surge of up to 40% in activity at some sites.