When Hindus visit Allahabad while on Pilgrimage to Varanasi, also known as Benares,one is ordained to take bath at the Triveni Sangam in Allahabad (Prayag), where the Rivers Ganges,Yamuna and Saraswati are in Confluence.
One goes deep into the Ganges and takes bath, where the Sarasvati River is supposed have underneath-invisible now.
The Vedic Civilization prospered on the banks of the River Saraswati,
The ancient Rig Veda speaks of River Sarasvati thus.
The sixth Mandala of the Rig Veda has 75 hymns, mainly to Agni and Indra. Most hymns in this book are attributed to the bārhaspatya family of Angirasas, especially to Bharadvaja. It is one of the “family books” (mandalas 2-7), the oldest core of the Rigveda.
Deities addressed besides Indra and Agni include the Vishvadevas, Pusan, the Asvins, Ushas (Dawn), the Maruts, Dyaus and Prthivi (Heaven and Earth), Savitar, Brhaspati and Soma-Rudra.
The rivers mentioned in the sixth Mandala are the Sarasvati, Yavyavati and Hariupiya. RV 6.61 is entirely dedicated to Sarasvati. In RV 6.45.31 the term Ganga occurs which may refer to the Ganges River