Tet is the most important Vietnamese holiday, celebrating the new year on the lunar calendar. It celebrates the beginning of spring and the beginning of a new year. The Tet holiday lasts for seven days, and starts on the twenty-third day of the twelfth month on the lunar calendar with Le Tao Quan; a Cay Neu is planted on this day. Then Le Giao Thua comes on the hour before midnight and is a transition period into the new year. And finally, on the first day of the new year, comes Tet Nguyen Dan; and the Cay Neu is taken down.