Nepal has four major river system with more than two - hundred fifty sizeable tributaries .The major rivers are: - The Sapta Kosi in the extreme eastern Nepali; the Narayani in the central Nepali; the Karnali in the western Nepal and the Mahakali in the far western Nepal. Arun rivers are one of the tributaries of river Sapta Kosi that flows in the Eastern Nepal. Besides being the only Hindu country in the world with all to myths and mysterious character, Nepal has more than one hundred different dialects speaking people belonging to various ethnic groups. Meeting there different ethnic groups of people during the of rafting is all a part of adventure.