Transport Secretary Chris Grayling has announced the location of the new lower Thames Crossing to accompany the current crossing at Dartford.
'Option C' or linking the A2 with the M25 has been revealed as the preferred option meaning a new tunnel will be built under the River Thames east of Gravesend.
The route will run from the M25 near North Ockendon, cross the A13 at Orsett before crossing under the river east of Tilbury and Gravesend.
A new link road will also be built which is designed to take traffic from the A2 near Shorne, close to where the route becomes the M2.
Up to 4.5 million heavy goods vehicles are expected to cross within the first year.
Highways England have backed this option as they believe it will reduce pressure on the Dartford Crossing.
The crossing could create up to 6,000 new jobs and boost the economy by more than £8billion, according to the government.
Mr Grayling said: "We are making the big decisions for Britain. The new Lower Thames Crossing, and other improvements in and around Dartford and Thurrock announced today, will further strengthen our economy while also creating thousands of jobs.
"The schemes announced today not only show we are taking decisions, we are planning upgrades and we are completing roads – making the lives of millions of motorists better."
Nearly 47,000 people took part in a consultation to find the most preferred method, with the majority going for option C.
Christian Brodie, chairman of the South East Local Enterprise Partnership, said: "This is excellent news for Kent and Essex, as these three announcements will have a significant economic impact. The investments announced will strengthen the resilience of our UK and European connections – imperative as we now move towards Brexit.
"However, the benefits go far beyond Kent and Essex. With the current Dartford Crossing already operating at capacity and freight traffic continuing to grow, the new crossing will also support the Government's wider economic aspirations for the Northern Powerhouse and Midlands Engine."