Although many areas in Calcutta were inhabited by those prostitutes outside those areas also.
On the south it was Kalighat to Khidirpur dock areas, in the middle-Calcutta it was Kalinga-Fenwick Bazar, on the far south in Kareya area many girls from different social-classes of Hindu-Muslim-Christian communities were engaged with this profession.
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Prostitution may be brothel-based or non-brothel based as in the case of call girls.For example, The red-light area which once existed opposite to the diagonal angle of Khanna Cinema Hall was of 'poor-class'.When they contacted customers, they asked them "Khat-e na Chot-e" ?Previously there were many Bengali prostitutes in Sonagachi.But now-a-days Rajasthani and Khamia-Nepalese prostitutes have gained in number.
More than that, there was no clear 'mark' or 'boundary-line' between the 'gentleman areas' and the 'prostitutes areas'.