Mbh 13.26.6a

"'"The Rishi crowned with success said, 'Those countries, those provinces, those retreats, and those mountains, should be regarded as the foremost in point of sanctity through which or by the side of which that foremost of all rivers, viz., Bhagirathi flows. That end which a creature is capable of attaining by penances, by Brahmacharyya, by sacrifices, or by practising renunciation, one is sure to attain by only living by the side of the Bhagirathi and bathing in its sacred waters. Those creatures whose bodies have been sprinkled with the sacred waters of Bhagirathi or whose bones have been laid in the channel of that sacred stream, have not to fall away from heaven at any time.[237] Those men, O learned Brahmana, who use the waters of Bhagirathi in all their acts, surely ascend to heaven after departing from this world. Even those men who, having committed diverse kinds of sinful deeds in the first part of their lives, betake themselves in after years to a residing by the side of Ganga, succeed in attaining to a very superior end. Hundreds of sacrifices cannot produce that merit which men of restrained souls are capable of acquiring by bathing in the sacred waters of Ganga. A person is treated with respect and worshipped in heaven for as long a period as his bones lie in the channel of the Ganga. Even as the Sun, when he rises at the dawn of day, blazes forth in splendour, having dispelled the gloom of night, after the same manner the person that has bathed in the waters of Ganga is seen to shine in splendour, cleansed of all his sins. Those countries and those points of the compass that are destitute of the sacred waters of Ganga are like nights without the moon or like trees without flowers. Verily, a world without Ganga is like the different orders and modes of life when they are destitute of righteousness or like sacrifices without Soma.