SB 10.10.4
antah pravisya gangayam
ambhoja-vana-rajini
cikridatur yuvatibhir
gajav iva karenubhih
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Within the waters of the Mandakini Ganges, which were crowded with gardens of lotus flowers, the two sons of Kuvera would enjoy young girls, just like two male elephants enjoying in the water with female elephants.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
People generally go to the Ganges to be purified of the effects of sinful life, but here is an example of how foolish persons enter the Ganges to become involved in sinful life. It is not that everyone becomes purified by entering the Ganges. Everything, spiritual and material, depends on one’s mental condition.