The shift toward community celebration happened in 1910, when a group of twelve friends in Guptipara, Hooghly, pooled money to organise a 'Barowari' puja — baro meaning twelve, yari meaning friends. This was the model for what we now call the Sarbojanin (universal, for all) Durga Puja: a celebration that belongs to the neighbourhood, funded collectively, open to everyone regardless of caste or wealth.

The Sarbojanin model spread rapidly through Bengal in the 1920s and 30s. By independence it was the dominant form. The competitive element — each para's puja trying to outdo the others in scale, creativity, and spectacle — emerged naturally and has never stopped escalating.

In 2021, UNESCO inscribed 'Durga Puja in Kolkata' on the Representative List of Intangible Cultural Heritage of Humanity. The inscription recognised not just the religious observance but the entire ecosystem around it: the artisans of Kumartuli who make the idols, the Dhaak players from Bishnupur who travel to Kolkata each year, the thousands of craftsmen who build the themed pandals, the communities that gather regardless of religion. When UNESCO said Durga Puja was a cultural heritage of humanity, they were describing something that has genuinely earned that description.

Maha Shashthi (October 17) — The Goddess arrives. Bodhon (awakening) ceremony is performed at dusk. The banana tree (Kola Bou) is installed as Shiva's second wife and kept near the main idol. The face of the Goddess is unveiled for the first time. For many Bengali families, Shashthi evening is when the Puja truly begins — the first time you see the idol and the pandal together, with the lights and the Dhaak.

Maha Saptami (October 18) — The Navapatrika ritual, popularly called Kola Bou snan (the banana tree's bath). Nine plants are tied in a sari, taken to a pond or river at dawn, bathed, and brought back to sit beside Ganesha. This represents the nine forms of Durga. Pushpanjali (flower offering) begins.

Maha Ashtami (October 19) — The most sacred day. Pushpanjali is performed three times. Kumari Puja — the worship of a young girl (usually between 6 and 12) as a living embodiment of the Goddess — is performed in many temples, most famously at the Belur Math. Sandhi Puja happens at the exact 48-minute juncture between Ashtami and Navami.

Sandhi Puja — 108 lamps and 108 lotus flowers are offered at the moment when Ashtami ends and Navami begins. This is the most intense ritual of the entire Puja — the moment when Durga took the Chamunda form to kill the demons Chanda and Munda simultaneously. The drumming is continuous, the smoke from 108 dhunuchi is dense, and the air in the pandal becomes something you don't forget.

Maha Navami (October 19, evening) — The Navami bhog — the largest communal meal of the Puja — is distributed. Hom (fire ritual) is performed. The mood shifts slightly: the Goddess is leaving tomorrow.

Vijayadashami (October 20) — Sindoor Khela in the morning, Bisarjan (immersion) in the afternoon and evening. This is the day that breaks a particular kind of heart. The idol that has been the centre of the neighbourhood's universe for five days is taken to the river. As it goes under, the tradition is to say: 'Asche bochhor abar hobe' — it will happen again next year.