Thousands of British motorists and passengers were again stranded for up to 12 hours while bomb disposal experts tackled a mysterious hazard on the carriageway.
The British M3 motorway, the main road between London and Southampton, was closed between junctions 9 and 11 after emergency services were called to the scene just before 4am this morning.
Witnesses reported motorists driving the wrong way down the hard shoulder, abandoning their vehicles altogether, or turning the carriageway into a makeshift playground while the Explosive Ordnance Disposal (EOD) team got to the bottom of the problem.
Social media users shared pictures of the scene near Winchester today, with one showing a man walking his dog on the hard shoulder, others playing golf, and another doing a handstand on the carriageway.
Hampshire Police said they were still unable to confirm the nature of the cargo, whether it was placed deliberately on the carriageway or whether it was an accident.
But it comes days after thousands sat in gridlock for up to 12 hours when Thames Valley Police closed the three-lane motorway of the M1 between junctions 14 and 15 because of a "suspicious object" - something police later said could have been highly corrosive hydrochloric acid, possibly placed deliberately.
Witness Jenna Keating, 31, a writer from Windsor, told the Press Association: "There are lots of people stranded here, people have got out of their cars to stretch their legs and things, but some are just turning round and going back down the hard shoulder.
"We actually spoke to police about this to see whether this was something we could do in the circumstances and they said 'absolutely not'.
"They also said the delay had been quite well advertised, although none of the four of us in the car saw anything until we were in it.
"I can't think it's a good idea to use the hard shoulder - there have been a couple of unmarked vehicles with sirens blaring coming up and using it, so it's pretty dangerous if there are cars coming in the other direction."
Manchester United fan Paul Hibbert was travelling with his friends to see his team play Southampton but decided to leave the coach and make the one-and-a-half-mile journey to Winchester station by foot, walking along the hard shoulder to junction 9.
The 53-year-old, from Manchester, said: "People here are driving up the hard shoulder.
"One of those idiots has hit a car that pulled out in front of him - it's chaos.
"We got the National Express at quarter past midnight to London and got the 8am bus to Southampton - it's 1pm now."
Mr Hibbert later made the game just in time to see his team open the scoring.
George Vitelis, stranded at Winchester service station since around 9.30am, said the incident brought out "the best of the British spirit".
He said: "I'm lucky because I'm in the service station, I have use of the facilities, it is lovely and warm and people are just getting on with things.
"There's not a lot we can do so some guys just took out their golf clubs and are just practising a few strokes.
"It's quite a strange situation - there are babies having their diapers changed next to the M3, guys playing golf, people having picnics.
"The sun is shining, the weather is warm, I'm quite happy here to be honest. It would be different if I was stuck in the car with a load of screaming kids, but I'm not.
"It's moments like this that you see the best of the British spirit.
"I was heading down to the boat show in Southampton but that probably isn't going to happen now. I'll just go tomorrow instead, it's no problem."
Commenting on the conduct of some drivers, RAC spokesman Rod Dennis said: "The hard shoulder is there for a reason and no matter how frustrating a long jam can be, it's vital people don't put themselves in unnecessary danger.
"The hard shoulder can be vital for emergency vehicles and we would strongly discourage anyone from using it unless they have broken down or have their own, genuine emergency."