<P> Patel is the namesake of many public institutions in India . A major initiative to build dams, canals, and hydroelectric power plants in the Narmada river valley to provide a tri-state area with drinking water and electricity and to increase agricultural production was named the Sardar Sarovar. Patel is also the namesake of the Sardar Vallabhbhai National Institute of Technology in Surat, Sardar Patel University, Sardar Patel High School, and the Sardar Patel Vidyalaya, which are among the nation's premier institutions . India's national police training academy is also named after him . </P> <P> The international airport of Ahmedabad is named after him . Also the international cricket stadium of Ahmedabad (also known as the Motera Stadium) is named after him . A national cricket stadium in Navrangpura, Ahmedabad, used for national matches and events, is also named after him . The chief outer ring road encircling Ahmedabad is named S P Ring Road . The Gujarat government's institution for training government functionaries is named Sardar Patel Institute of Public Administration . </P> <P> Rashtriya Ekta Diwas (National Unity Day) was introduced by the Government of India and inaugurated by Indian Prime Minister Narendra Modi in 2014 . The intent is to pay tribute to Patel, who was instrumental in keeping India united . It is to be celebrated on 31 October every year as annual commemoration of the birthday of the Iron Man of India Sardar Vallabhbhai Patel, one of the founding leaders of Republic of India . The official statement for Rashtriya Ekta Diwas by the Home Ministry of India cites that the National Unity Day "will provide an opportunity to re-affirm the inherent strength and resilience of our nation to withstand the actual and potential threats to the unity, integrity and security of our country ." </P> <P> National Unity Day celebrates the birthday of Patel because, during his term as Home Minister of India, he is credited for the integration of over 550 independent princely states into India from 1947 - 49 by Independence Act (1947). He is known as the "Bismarck of India". The celebration is complemented with the speech of Prime Minister of India followed by the "Run for Unity". The theme for 2016 celebrations was "Integration of India". </P>

Who called sardar patel as iron man of india
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