Markandeya Purana and Brahmanda Purana divide Jambudvipa into four vast regions shaped like four petals of a lotus with Mount Meru being located at the center like a pericarp. The city of "Brahmapuri" is said to be enclosed by a river, known as "Akash Ganga". "Akash Ganga" is said to issue forth from the foot of Lord Vishnu and after washing the lunar region falls "through the skies" and after encircling the Brahmapuri "splits up into four mighty streams", which are said to flow in four opposite directions from the landscape of Mount Meru and irrigate the vast lands of Jambudvipa.