Ash Wednesday, in the Christian church, the first day of Lent, occurring six and a half weeks before Easter (between February 4 and March 11, depending on the date of Easter). Ash Wednesday is a solemn reminder of human mortality and the need for reconciliation with God and marks the beginning of the penitential Lenten season.
https://www.britannica.com/topic/Ash-Wednesday-Christian-holy-day

