NEW DELHI - The 45-day-long grand spiritual festival "Maha Kumbh" began in Prayagraj, a town in India's northern state of Uttar Pradesh, on Monday.

According to an estimate, nearly 5 million people, including Hindu saints, took the holy dip in the "Triveni" or "Sangam", the confluence of three rivers, Ganga, Yamuna and Saraswati, by 09:00 am. The first day was marked by the "Paush Purnima" festival.

Around 15 million devotees were expected to take the holy dip through the day.

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The first "Shahi Snaan" (Royal Bath) would take place on Tuesday, and thousands of Hindu religious and spiritual leaders from various sects and groups would arrive in large processions to take the holy dip.

People from across India and other nationalities congregated to take the holy dip on Monday, said an official overseeing the arrangements. Thousands of temporary tents with all accommodation facilities have been installed at the venue.

The festival falls after every 12 years. Elaborate security and accommodation arrangements have been made for the safety of devotees, said the official.

An estimated 400 million devotees and tourists were expected to visit Prayagraj over the next 45 days.

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Prime Minister Narendra Modi shared his greetings on the occasion. "Maha Kumbh 2025 commences in Prayagraj, bringing together countless people in a sacred confluence of faith, devotion and culture. The Maha Kumbh embodies India's timeless spiritual heritage and celebrates faith and harmony," Modi posted on social media.

"I am happy to see Prayagraj abuzz with countless people coming there, taking the holy dip and seeking blessings. Wishing all pilgrims and tourists a wonderful stay," he said.