The following words by The Source Project: 
“This
is just the beginning, the build up to the Durga Puja in Kolkata. Every
year, for for months throughout the rainy season, artists, workers and
families prepare for the largest event of the year. By using local
materials, clay from the river and straw from the rural communities,
some of the most talented artists create some of the largest and most
beautiful idols. Communities and families then purchase, worship then
submerge them in the Hooghly River. This is just the first part of this
devotional wonder…

Durga Puja festival marks the victory of Goddess Durga over the evil
buffalo demon Mahishasura. Thus, Durga Puja festival epitomises the
victory of Good over Evil.

Durga Puja is widely celebrated in the Indian states of Assam, Bihar,
Jharkhand, Orissa, Tripura and West Bengal, where it is a five-day
annual holiday. In West Bengal and Tripura, which has majority of
Bengali Hindus it is the biggest festival of the year. Not only is it
the biggest Hindu festival celebrated throughout the State, but it is
also the most significant socio-cultural event in Bengali society. Apart
from eastern India, Durga Puja is also celebrated in Delhi, Uttar
Pradesh, Maharashtra, Gujarat, Punjab, Kashmir, Andhra Pradesh,
Karnataka and Kerala. Durga Puja is also celebrated as a major festival
in Nepal and in Bangladesh where 10% population are Hindu. Nowadays,
many diaspora Bengali cultural organizations arrange for Durgotsab in
countries such as the United States, Canada, United Kingdom, Australia,
Germany, France, The Netherlands, Singapore and Kuwait, among others. In
2006, a grand Durga Puja ceremony was held in the Great Court of the
British Museum.

The prominence of Durga Puja increased gradually during the British Raj
in Bengal. After the Hindu reformists identified Durga with India, she
became an icon for the Indian independence movement. In the first
quarter of the 20th century, the tradition of Baroyari or Community Puja
was popularised due to this. After independence, Durga Puja became one
of the largest celebrated festivals in the whole world.

Durga Puja also includes the worship of Shiva, who is Durga’s consort
(Durga is an aspect of Goddess Parvati), in addition to Lakshmi,
Saraswati with Ganesha and Kartikeya, who are considered to be Durga’s
children. Worship of mother nature is also done, through nine types of
plant (called “Kala Bou”), including a plantain (banana) tree, which
represent nine divine forms of Goddess Durga. Modern traditions have
come to include the display of decorated pandals and artistically
depicted idols (murti) of Durga, exchange of Vijaya greetings and
publication of Puja Annuals.”
~ VIA Vimeo