By Tom Gillespie @TomGillespie1
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The seedy world of Sonagachi in Kolkata, India, is swamped with hundreds of multi-storey brothels, housing roughly 14,000 prostitutes from all over India.
Many of the sex workers have been trafficked into the profession, and are forced to sleep through the day and work tirelessly through the night.
Other women have made a conscious decision to join the trade with the promise of higher earnings than their previous position.
While checking the playlist on her newly bought smartphone, a Sonagachi sex worker named Baishaki said: “I used to work as a domestic help where I earned about £15 per month, whereas now I am earning £170 - £180.
“I have come across people who have taken this profession up as a family tradition.”
Kolkata in West Bengal is nicknamed the City of Joy and is regarded as one of the most beautiful cities in India.
But the sprawling streets and nocturnal life of Sonagachi appear to buck the trend.
At weekends the red light district buzzes with customers of all ages from a range of different professions.
Each sex worker has their own story, with some claiming to have found a better life since arriving in Sonagachi.
Prostitute Bina, 30, said: "I was married to a drunkard for seven years.
“He used to beat me up every day. I was staying with him for the sake of my daughter.
"I have found love with one of my customers and I am very happy about it."
Although the sex workers earn good money, local businessmen take advantage by upping what would be the normal price of commodities.
Maya Banerjee, 72, spent years working as a prostitute but says she is now too old for the sex trade.
Despite no longer being able to work, Maya chooses to remain in the red light district where she has spent most of her life.
She said: "A simple fish that costs 160 rupees per kilogram everywhere else is sold at 250 rupees per kilogram here. This is how their life goes on.”
Several NGOs and government organisations operate in Sonagachi to help prevent the spread of STDs - including AIDs.
Although prostitution is illegal, the trade flourishes and the women who work there are shunned by society.
The sex working community often falls victim to rapes, robberies, and extortion.
Kabita, a sex worker turned social worker, said: “Legalising prostitution would help the government earn good revenue and it can reduce the number of crimes that occur in Sonagachi.”