According to the description of geography in the Purana, each of these was divided into a number of varsas or subcontinents. These dvipas were surrounded by seven oceans containing water which salt, sugarcane-juice, wine, clarified butter, curd, milk and good drinking water mixed in the water of the ocean.
The Jambu dvipa, which occupied the central position, among the seven dvipas, had in its middle a golden mountain called Meru, with a ring of land. The Mount Meru is in the central and from which a number of other mountains including the Himalaya radiated in different directions like the petals of a lotus. According to the geography of Puranic tradition this dvipa was divided into nine varsas or subcontinents, one of which was Bharata-varsa (India). Moreover according to the Puranic tradition, the Mount Meru is considered as the axis of the spherical earth.
The Puranas provide ample information about all the seven dvipas, thereby gives the description of the geography of the universe during its creation. The Puranas supply the information about the measurements, their mountains and rivers, their residents, their presiding deities, the longevity and general standard of morality of the people, and other details. But surprisingly the Puranas are found to give special emphasis to the physiographic description of Jambu dvipa and, more particularly, of Bharata varsa, which in early times occupied a much bigger area. In the ancient times the land of Bharata varsa had been praised as the karma bhumi or place of work. It is also considered as the blessed land of God or the creator Brahma. It was a favorable land for those who aspire for heaven or final liberation.
Jambu Dvipa is separated from the next dvipa Plakshadvipa by an ocean of salt. Plakshadvipa in turn forms a concentric circle surrounding the Jambu Dvipa and so on to give a proper form to the total seven continents. These continents are divided from the neighbor continents by ocean of different composition. Apart from the thorough description of these two dvips, the information about the other dvipas is too small.
The Puranic geographical accounts though provide ample information about the topographical features of the universe, when it was created, it has several shortcomings according to the modern scholars. According to them, the description provided by the Puranas is considerably influenced by mythology instead of the scientific description. Hence the Puranic description has undergone several modifications and changes in the later years.