Bhopal was referred to as “Bhoj Pal” in earlier times, Bhoj being the legendary King Bhoj Deva, and Pal being a dam. Raja Bhoj Deva, the most illustrious of the Parmar rulers, was one of the greatest kings of ancient India. He ranks with the legendary Vikramaditya of Ujjayani. In fact, both the names has gathered vast wealth of legend and knowledge around them. Bhoj deva’s name has become a household word in India not only as a soldier, but also as a builder, a scholar, an author and a great patron of learning. He ascended the throne approximately in 1010 A.D. and reigned till 1055 A.D as per from the Modasa copper plate inscription. He was a great warrior and carried his sword to the four corners of India. He also enunciated principles of art, architecture and vastushastra in his famous treatise Samarangarasutradhara and navigation, ship-building and marine engineering in Yuktikalpatru.The famous lake of bhopal known as the upper lake or the “Bada Talab” or “Badi Jheel” has been created by 300′ wide wall of dry masonry made of big boulders tapering to approx. 500’at the base. The wall holds the waters of Kolans and Kujhaman rivers to form Bara Talab with a spread of 30.72 sq. km. According to a legend, Raja Bhoj was suffering from a skin ailment which could not be treated by manu learned physicians. One Sadhu (holy men of India) then advised that the king takes bath everyday at an auspicious hour in waters from 365 springs. The location has been chosen to perfection, where a minimum effort would have given the maximum benefits.The dam is a circular/cylindrical structure which has been created using dry masonary of huge boulders. Over time, bhopalis forgot that the dam has been constructed by human being, and took it to be natural. However, it was overserved in recent years that the lake is not filling up completely even after good rainfall was received by the catchment area. The Archiological Survey Of India, On entering the tunnel, found that the tunnel was leaking badly and many boulders from this dry masonary work had fallen down. Moreover there were huge trees which had grown over years on this embankment, and the roots of these trees penetrated the tunnel. The floor of the tunnel was filled deep with mud. Water was flowing continuosly from Upper lake to the Lower lake, which was supposed to let out only the spillage water. The tunnel has been fortified using cement, the trees has been cleared and the bigger boulders has been replaced.
Bhojpur, about 28 km from Bhopal, has a magnificient Shiva temple. The incomplete Shiva temple is often referred to as the Somnath of the East, and the ramps for construction are still visible. On the west of Bhojpur temple once lay a vast lake, but nothing remains except the ruins of magnificent old dam by which its waters were contained. The remains of this dam is similar in structure to the dam found at Bhopal, and is attributed to Raja Bhoj.
The site was chosen with great skill, as a natural wall of hills enclosed the whole area except for two gaps, 100 yards and 500 yards in width respectively. These were closed by gigantic earthen dams, faced on both sides with enormous blocks of sandstone, many being 4 feet long, 4 feet broad and 2.5 feet thick, set without mortar. The smaller dam is 44 feet high and 300feet thick at the base, the larger dam 24 feet high with a flat top 100 feet broad. These embankments held up and expanse of water of about 250 square miles. The lake was destroyed by Hoshang Shah (1405-34) who established the near by Hoshang Abad. The water sheet provided for a big range of forest inhabited by dacoits, who entered the territories of Hoshan Shah. To eliminate these dacoits, he order the lesser dam to be cut through. According to a Gond legend, it took an army three months to cut the dam, while it took three years for the water of the lake to flow out. It’s bed was not habitable, it is said, for thirty years afterwards. The climate of the region is said to have been considerably altered by the removal of this vast sheet of water.