Modi, who arrived in Gujarat post midnight, sought his mother's blessings early Tuesday morning.
He then landed in Kevadiya in Narmada District in a chopper to perform pooja at the Sardar Sarovar Dam site. The dam venue has been decorated ahead of the Prime Minister's visit.
He also visited the Khalvani Eco-Tourism site in Kevadiya and strolled across the rope bridge that was constructed across the river there for sports enthusiasts.
He took a safari ride on a special jeep with zebra-patterns at the Jungle Safari Tourist Park in Kevadiya. Watched the animals there, and took a stroll around to soak in the beauty of the safari park.
Later, the Prime Minister visited the Khalvani Eco-Tourism site in Kevadiya and a Cactus Garden. Gujarat Chief Minister Vijay Rupani and Governor Acharya Devvrat were also present. He took a stroll along the banks of the Sardar Sarovar Dam site.
At the Butterfly Garden in Kevadiya, the Prime Minister smiled as he released a large basket full of butterflies into the park.
He also visited the Ekta Nursery, situated in the vicinity of the Statue of Unity. The nursery manufactures various traditional eco-friendly products and offer a live demonstration of the manufacturing process to visitors.
Later Modi offered prayers at the Sardar Sarovar Dam site.
Earlier, before landing at Kevadiya, the Prime Minister did an aerial survey of the Statue of Liberty. He tweeted: "Have a look at the majestic 'Statue of Unity', India's tribute to the great Sardar Patel."
The pooja he performed at the dam was part of the Namami Devi Narmada Mahotsav which is being organised by the Vijay Rupani government to mark the rise of water levels 138.68 metres in the Sardar Sarovar reservoir. The pooja is also being performed at 5,000 different places on the banks of the Narmada.
The water has risen to this level for the first time after its height was raised in 2017. The dam was inaugurated on this day in 2017.
The BJP has announced 'Seva Saptah (service week) and the workers are organising blood donation camps and other public service initiatives.
Prime Minister Modi has been greeted by large number of people across the country. Congress Interim President Sonia Gandhi wished him a healthy, happy and long life.
Andhra Pradesh Chief MInister Y.S. Jagan Mohan Reddy also wished Modi: "Warmest birthday greetings to our honourable Prime Minister. Wishing him long, healthy and successful life ahead in the service of the Nation," he said.
Union Ministers and BJP leaders, including Amit Shah, Rajnath Singh, Nirmala Sitharaman also greeted him.
( With inputs from IANS )