The worship of mother goddess is one of the three current forms of worship in Hinduism. There is well established archaeological evidence of continuous worship at Baghor from late upper paleolithic period (c. 9000–8000 BCE). This is the oldest archaeological evidence that is based on physical structures and not based on other forms of enquiry like linguistic evidence.
Reference:
Misra, V. N. "Prehistoric human colonization of India." Journal of Biosciences26.4 (2001): 491-531. [Online] available from here
Actual work:
Kenoyer, Jonathan M. Shell Working industries of the Indus civilization: an archaeological and ethnographic perspective. Diss. University of California, Berkeley, 1983.
Update:
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