After a gruelling march north, tempers are shorter than normal but then there is little here -- the towers of smoke rising from a battered Baghdad are not far off in the distance -- that resembles anything like normal.

Iraqis unable to stand another moment in the city are fleeing south, packed into old and creaky cars with their most essential belongings. Some cars bear white flags of peace, others make do with toilet paper.

Those getting away may see some of the scenes we have witnessed on our nearly month-long trudge, a time when there have been no showers, little sleep and occasional moments of horror.

Along Route Six heading west into Baghdad, an industrial suburb is littered with the wreckage of war -- the hulks of burnt-out trucks, Iraqi howitzers, tanks, and now and again a body. Buildings have been strafed and shot-up.

In some areas, relatively ritzy homes and even a golf course suggest a now-abandoned stronghold of Saddam Hussein's Baath party, which has helped enforce his 24-year grip on the nation.

The marines stop occasionally to rifle through the better houses, sometimes finding a bag of small weapons.

Mindful of the suicide bombings which have already killed some of their colleagues elsewhere, and the Iraqi troops perhaps hiding amid civilians, the marines rebuff the children massed on the side of the road, trying to sell drinks and cigarettes.

An even bigger temptation is the water of the Tigris river, whose waters beckon to crusty soldiers who can't remember the last time they stood under the running water that could wash away the black grime packed into their skin.

"I'm desperate to take my clothes off and jump in the river," says corpsman Done Alcantara, but he cannot.

"I'm the same person that says don't accept local food, local drinks and local water so I can't set a bad example," he says.

His colleague Ernest Hayes says they have trained for these temperatures, which have surpassed 40 degrees Celsius (104 Fahrenheit), but adds, "It's still terribly hot. I lost five pounds (two kilos) in water weight in one day."

The heat had eased a bit Sunday after two particularly brutal days and, while the change is welcome, the marines are still far away from a comfortable bed -- and getting ever closer to what could be a bloodbath in Baghdad.

"Baghdad could be the scene of 100 Nasiriyahs," says one senior officer, naming the southern Iraqi city which saw ferocious fighting during the first week of the war.

Up ahead, an oil facility blazes after being hit by an air strike, throwing more heat and smoke into the air and serving as a reminder that -- as US commanders keep carefully pointing out -- the war remains far from over.

A favourite catchphrase now is that the quickest way to get home is to arrive in Baghdad and wage the battle. The urge, maybe stronger than all the other urges now, is to get their business over with.

"Mentally I'm prepared for Baghdad," says Private Travis Cotner. "We're ready to take it and looking forward to finishing this off and we're seeing this as the end of the war."

SPACE.WIRE