They expected tea, not firefights.
But the three female Marines and their patrol were shot at late on a recent day, when a burst of Kalashnikov rifle fire came from a nearby compound. The group hit the ground, and aimed its guns across the fields of cotton and corn.
In their sights they could see the source of the blast: an Afghan man who had shot aimlessly from behind a mud wall, shielded by a half-dozen children.
The women held their fire with the rest of the patrol so as not to hit a child, waited for the all-clear, then headed back to the base, survivors of yet another encounter with the enemy.
"You still get that same feeling, like, 'Oh, my gosh, I'm getting shot at,' " said Lance Cpl. Stephanie Robertson, 20, speaking of the firefights that have become part of her life in Marja.
Six months ago, Robertson arrived in Afghanistan with 39 other female Marines from Camp Pendleton, Calif., as part of an unusual experiment of the American military: sending full-time "female engagement teams" out with all-male infantry patrols in Helmand Province to try to win over the rural Afghan women who are culturally off limits to outside men.
As new faces in an US counterinsurgency campaign, the female Marines, who volunteered for the job, were to meet with Pashtun women over tea in their homes, assess their need for aid, gather intelligence, and help open schools and clinics.
They have done that and more, and as their seven-month deployment in southern Afghanistan nears an end their "tea as a weapon" mission has been judged a success. But the Marines have also had to use real weapons in a tougher fight than many expected.
Here in Marja, the female Marines have daily skirted the Pentagon rules restricting women in combat.
None of the 40 women have been killed or seriously injured, and a number have worked in stable areas, but many have seen good friends die.
One of the women, Corporal Anica Coate, 22, was on patrol in early September in southern Marja five feet behind Lance Cpl. Ross S. Carver, 21, when he was shot through the mouth and killed. A week later she said she would not volunteer for the female engagement teams again. "It's not the living conditions, it's not the mission, it's this," she said, gesturing toward a memorial display of boots, rifles and dog tags belonging to the dead Marines. She was, she said quietly, "too much of a girl to deal with these guys getting killed."