With a total population of 1.7 million, Bhopal is the 17th largest city of India and the 6th largest Hindi speaking city. Highest employment in Bhopal District is in Railway workshops, manufacture of electrical, engineering, chemical and metal products. Out of the entire workforce, 77% are employed in the above mentioned Industrial segment, 20% in Agriculture and the remaining 3% as Household workers. Bhopal has not been a big agricultural district since the city nestles in the hilly terrain of the Vindhyan range and Malwa plateau. Hillocks of different altitudes are situated along the southwest and northwest portion of the city, forming a continuous belt from Singarcholi up to the Vindhyanchal range. The height of Singarcholi near Lalghati is 625 metre, which is the maximum height in this area. The general ground level is nearly 460 metre along the southeastern and northeastern portion of the city. Bhopal is known as the city of Lakes. According to folklore, Bhopal was founded in the 11th century by the Paramara King Bhoja, who ruled from his capital at Dhar. This theory states that Bhopal was originally known as Bhojpal after a dam (pal) was constructed by the kings minister. An alternative theory states that the city is named after another king called Bhupala (or Bhupal). Bhopal has many archaeological and historical remains indicating the importance of this city over the millennia. In the pre-Independence era, the state of Bhopal was the second-largest Muslim-ruled princely state after Hyderabad. After the independence of India in 1947, Bhopal state was taken over by the Union Government of India on 1 June 1949. The memory of the December 1984 gas leak at the Union Carbide pesticide plant still lingers on amidst the people of Bhopal.