'Kothin Chibor Dan' is a Buddhist ceremony on which occasion 'viksus' are given 'chibor' or cloth to wear. Buddhists believe that this is the best of all gifts. Chibor, the cloth that viksus wear, may be of any six colours: those of a tree's roots, trunk, bark, dry leaves, fruit or flower.

However, the viksu community prefer to wear cloth the colour of red flowers, as it is different from the cloth that ordinary people wear and also because it does not have attractive designs. According to Raja Barrister Debashish Roy, Circle Chief of Chakma community, Kothin Chibor Dan develops social harmony, creates cooperation and teaches the people how to improve friendship among themselves.

Elaborate programmes are chalked out on the occasion, including Buddha. Puja, Ful Puja, Sibli Puja, Feeding the Monks, Astaporiskardan, taking Panchshil and Astashil and praying for world peace. The two-day long "Kothin Chibor Dan Utsab"-the greatest religious festival of the Buddhist community is celebrated with religious fervour at Rangamati Rajban Bihara in the Rangamati hill district.

The religious festival is organized by Rangamati Rajban Bihara Upasak Upasika Parishad. On the eve of the function Buddhist people from three hill districts begin gathering at Rangamati Rajban Bihara Area to participate in the festival.

Many visitors and tourists from home and abroad gather to enjoy the festival. Every year about four hundred thousand people of all communities from the three hill districts (Bandarban, Khagrachari and Rangamati) in greater Chittagong Hill Tracts as well as from other parts of the country come to celebrate and enjoy this festival.