Durga Puja is the most celebrated festival in West Bengal and among the Bengalis all around the world. The most important days of Durga Puja are the seventh, eighth and ninth days of the festival and the tenth day, which is the last day of the celebration. With the first rays of the sun on Saptmi (the seventh day), a tree is dressed as the Goddess Durga herself in yellow silk cloth with a red border. The tree deemed to be the Goddess then becomes the spotlight attraction for the rest of the festival. The priest carries the tree in a grand procession to the Durga Puja pandal (big tent) accompanied by the drummers to welcome the Goddess. A platform is set up with an idol of Lord Ganesha already seated there. The tree-goddess is then installed beside the God of good fortune and then worshipped. The next day or Ashtami was traditionally the buffalo sacrifice day to commemorate the victory of the Goddess over the buffalo-demon Mahishasura. However, there are no more sacrifices today except for a few incidents that may occur at the orthodox villages in the remotest areas but the Indian government and the modern wave of animal love and compassion discourage them too.

The ninth day of the festival is characterized by the all-day 'pujas' and 'shaloka-recitals' and a 'Maha Arti' that is considered a formal end of religious customs. Merriment, music and dance fill the rest of the day. On the tenth day, grand processions are taken out, full of colors and dance, where the Durga idols are taken for 'visarjan' (immersion in a pond, river or sea). These much-celebrated idols also have traditions associated to their making. However, the most fundamental rule is based on the earlier theory of cyclical regeneration, as it required all the things used in the making of these idols to come from the river itself. However, people overlooked the rule for many years resulting in the pollution of water due to harmful paints and chemicals used in the making of these idols but now, this rule has been revived by the nature lovers again. Dussehra is also associated with the harvest festival of the agrarian societies and is believed to be the beginning of New Year in some communities.