As their convoy reached the barbed wire at the Khabari border crossing out of Iraq, the soldiers whooped and cheered. Then they scrambled out of their stifling armoured vehicles, unfurled an American flag and posed for group photos.
For these troops of the 4th Stryker Brigade, 2nd Infantry Division, it was a moment of relief fraught with symbolism. Seven years and five months after the US-led invasion, the last American combat brigade was leaving Iraq, well ahead of President Barack Obama's August 31 deadline for ending US combat operations there.
When 18-year-old Spc Luke Dill first rolled into Iraq as part of the US invasion, his Humvee was so vulnerable to bombs that the troops lined its floor with flak jackets.
Now 25 and a staff sergeant after two tours of duty, he rode out of Iraq in a Stryker, an eight-wheeled behemoth encrusted with armour and add-ons to ward off grenades and other projectiles.
"It's something I'm going to be proud of for the rest of my life -- the fact that I came in on the initial push and now I'm leaving with the last of the combat units," he said.
He remembered three straight days of mortar attacks outside the city of Najaf in 2003, so noisy that after the firing ended, the silence kept him awake at nights. He recalled the night skies over the northern city of Mosul being lit up by tracer bullets from almost every direction.
Now, waiting for him back in Olympia, Washington, is the "Big Boy" Harley-Davidson he bought from one of the motorcycle company's dealerships at US bases in Iraq -- a vivid illustration of how embedded the American presence has become since the invasion of March 20, 2003.
But that presence is far from over. Some 50,000 troops will stay another year in what is designated as a non-combat role. They will carry weapons to defend themselves and accompany Iraqi troops on missions, but only if asked. Special forces will continue to help Iraqis hunt for terrorists.
So the US death toll -- at least 4,415 by Pentagon count as of yesterday -- may not yet be final.
The Stryker brigade, based in Joint Base Lewis-McChord in Washington state and named after the vehicle that delivers troops into and out of battle, has lost 34 troops in Iraq.
It was at the forefront of many of the fiercest battles, including operations in eastern Baghdad and Diyala province, an epicentre of the insurgency, during the 2007 "surge".
It evacuated troops at the battle of Tarmiyah, an outpost where 28 out of 34 soldiers were wounded holding off militants.
Before the August 31 deadline, about half the brigade's 4,000 soldiers flew out like most of the others leaving Iraq, but its leadership volunteered to have the remainder depart overland. That decision allowed the unit to keep 360 Strykers in the country for an extra three weeks.
US commanders say it was the brigade's idea, not an order from on high.
The intent was to keep additional firepower handy through the "period of angst" that followed Iraq's inconclusive March 7 election, said brigade chief Colonel John Norris.
It took months of preparation to move the troops and armour across more than 300 miles of desert highway through potentially hostile territory.
The Strykers left the Baghdad area in separate convoys over a four-day period, travelling at night because the US-Iraq security pact -- and security worries -- limit troop movements by day.
Along the way, phalanxes of American military Humvees sat at flyovers, soldiers patrolled the highways for roadside bombs and Apache attack helicopters circled overhead as the Strykers refuelled alongside the highway.
Chief Warrant Officer 3 Gus McKinney, a brigade intelligence officer, said the biggest threat was roadside bombs planted by Shi'ite extremist groups with a strong foothold in the south.
But except for camels straying into the road, and breakdowns that required some vehicles to be towed, there were no incidents.
The worst of the ride was conditions inside the Strykers -- sitting for hours in a cramped space -- and the temperatures outside that reached 50C.
The driver's compartment is called the "hellhole" because it sits over the engine and becomes almost unbearably hot. The vehicle commander and gunner can sit up in hatches to see the outside world. At the tail end are hatches for two gunners. Eight passengers -- an infantry squad in combat conditions -- can squeeze in the back.
Riding as a passenger felt a bit like being in a Second World War-era submarine -- a tight fit and no windows. The air conditioning was switched off to save fuel on the long ride south to Kuwait. Men dozed or listened to music through earphones.
When the convoy finally reached the sandy border, two soldiers, armed and helmeted, jumped off their vehicle and raced each other into Kuwait.
Once out of Iraq, there was still work to be done. Vehicles had to be stripped of ammunition and spare tyres, and eventually washed and packed for shipment home.
For Spc Dill, who reached Kuwait with an earlier convoy, the withdrawal engendered feelings of relief. His mission -- to get his squad safely out of Iraq -- was accomplished.
Standing alongside a Stryker, his shirt stained with sweat, he remembered the men who were not there to experience the day with him.