"This leads us to the question of the Indus religion. Many scholars ,both foreign and Indian, are very reluctant to find any trace of modern Hindu rituals and beliefs in the finds which have been interpreted as evidence of Indus religion. Two facts, however, cannot be wished away – regrettably from the point of view of this group of people. One is the indubitable presence of Siva in the form of linga-like stones found both at Mohenjodaro and Harappa, a distinctively phallic stone column at Dholavira, a seated ithyphallic stone figure from the same site, the famous ‘Siva-Pasupati’ figure on a seal, and the terracotta representation of a Siva-linga set in ‘Yoni-patta’ at Kalibangan. The second such evidence is the widespread presence of sacrificial pits at Lothal, Kalibangan , Banawali , Rakhigarhi and possibly a few other sites. These pits possibly have variations of their own. Their shapes and contents may also vary from site to site. However, their generic similarity with the ‘havan kundas’ which many devout people still dig up every day, light fire in, and pour offerings on, them is undeniable."
January 1, 1970
https://en.wikiquote.org/wiki/Religion_of_the_Indus_Valley_Civilization