How long has advent been around for?

Advent has been observed for over a thousand years, with its origins dating back to the 4th or 5th century in the Christian tradition. Initially, it served as a time of preparation for the celebration of the Nativity of Christ at Christmas. The modern form of Advent, which lasts four weeks, was established by the 19th century. Today, it is widely recognized in many Christian denominations around the world.