The A229 south-bound has fully reopened more than 10 hours after two vans crashed near the Lord Lees roundabout.
The crash happened between the Buckmore Park turn-off at Blue Bell Hill and Chatham Road at around 6.15am, with tailbacks on the A229 to J3 for the M2 for Chatham and Rochester.
There were also delays on the Maidstone Road to B2097 at Bridgewood Roundabout, near the Shell station.
The road was initially closed while emergency services dealt with the crash and later partially re-opened while repairs were carried out to the crash barrier.
Highways officials confirmed all lanes were clear by 4.26pm.