Authorities, which include the UK Border Force, intercepted a consignment that was intended for an industrial unit in Penistone on May 20, 2020.
It contained 19kg of Class A drugs - including 13kg of cocaine with a street value of more than £1.1m, and 6kg of heroin with a street value of almost £300,000.
Following more searches of the Penistone building, a further 15kg of Class B drugs were found including ketamine and even more cocaine.
Police searches at the home addresses of the three defendants found more than £31,000 and ¬ 13,000.
On Monday, three men were jailed for a combined 36 years at Sheffield Crown Court.
Jonathan McAllister, 29, from Barnsley, was sentenced to 20 years for importing Class A drugs, supplying Class A drugs, possession with intent to supply Class B drugs and money laundering.
Christopher McAllister, 33, from Sheffield was sentenced to 14 years and 24-year-old Connor Bodkin was sentenced to 12 years.
The Yorkshire and Humber Regional Organised Crime Unit (ROCU) has welcomed the sentencing of the men.
Detective Superintendent Paul Greenwood said: “We welcome the sentences given to these men for their roles in smuggling and selling very significant amounts of Class A drugs in both Yorkshire and the wider UK.
“This long running investigation with our partners uncovered a major drug conspiracy and is a real example of the very close work carried out between police, and partner agencies to combat this kind of organised crime.
“In this case the males attempts to import significant amounts of drugs from Europe into the UK raised flags with the UKBA and led to the investigation which cracked this criminal conspiracy.”
“We would urge anyone across Yorkshire and Humber who has information about drug dealing in their communities to contact their local police force or the independent Crimestoppers charity anonymously on 0800 555 111.”