Bihu
The most prominent celebration in Assam is Bihu, which is actually a collection of three festivals: Rongali in April, Kongali in October, and Bhogali in January. The most prominent of the three festivals marking the Assamese New Year and spring festival is Rongali Bihu.
While Bhogali Bihu is all about food, Kongali Bihu is a bit dreary, thrifty, and an animistic holiday that represents a season of limited supplies.
Bihu is a harvest celebration commemorating the change in the Sun's solstice. The Sun, when it starts its transitory phase towards the north, is widely appreciated across the country for its great impact.