Video report by North of England Correspondent Amy Welch
More than 580 tonnes of items - including clothes, drugs and illicit tobacco - were found in raids on 207 shipping containers on the outskirts of Cheetham Hill.
Greater Manchester Police (GMP) estimated the loss to criminals to be about £870 million.
Police said the "monumental" haul, gathered over the past 14 days, also included nitrous oxide canisters and counterfeit vapes from a storage unit.
The crackdown on fake goods is part of Operation Vulcan which has shut down 100 shops in Manchester.
GMP said it was the largest single seizure in Europe in almost two decades.
The force said the searches followed a covert operation combined with intelligence from the community and involved 100 officers working with multiple agencies.
GMP said it was now tracing where the items originated and working to ensure those involved were arrested.
Det Insp Christian Julien, one of Operation Vulcan's specialist officers, said the "largest raid to date" put GMP "on to the global stage, placing us in the top three worldwide for a single seizure of counterfeit items".
He said: "I hope that our work so far has shown the true scale of the counterfeit trade in the UK, the majority of which was on our doorstep here in Manchester.
"It’s important to recognise the serious impact of sophisticated and large-scale counterfeit operations like this and I would like to take this opportunity to remind members of the public of its links to serious organised crime.
"It isn’t a bargain so please be under no illusions - this type of crime is not victimless.
"Criminals are making vast amounts of money from this trade which is being funnelled into fuelling further criminality, exploitation, and misery not just in Manchester, but across the world.
"I’d like to thank each and every officer from across the force who came out to support the operation, and our partner agencies who have diligently contributed to the intelligence gathering and execution.
"At its heart, Operation Vulcan is a partnership effort, and everything we have achieved is down to the unrelenting efforts of our team and the unwavering support from partners."
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