Less than a year after most of them returned from a deadly deployment to Iraq, a battalion of Hawai'i-based Marines will return to war, shipping off to Afghanistan early next year.

Nearly 1,000 Kane'ohe Marines with the 1st Battalion, 3rd Marine Regiment, will deploy on a seven-month mission in Afghanistan's rugged mountains.

In anticipation of their deployment, they have increased their training at Marine Corps Base Hawai'i. Yesterday, about 600 members of the battalion completed a 12-mile hike, or "hump" as they call it, in full combat gear — body armor, weapons, heavy boots and a 35-pound backpack.

They are working harder now than they did before their last deployment. In September, the Marines will travel to California for about six weeks of training in Bridgeport and Twentynine Palms.

The relatively quick turn-around of deployments is becoming the norm within the Marines. The battalion learned about their new mission months ago while still in Iraq.

They will take with them to Afghanistan valuable combat experience as well as an intimate understanding of the true cost of war.

Fifty members of the battalion died in Iraq, including 17 killed when the Marines took the fight to Fallujah last fall. Another 26 Marines died when their helicopter crashed in a sandstorm in January.

More telling, perhaps: 157 Marines from the battalion have received a Purple Heart.

Sgt. Michael J. Valora, a section leader with a weapons company, is unfazed by the thought of a second deployment.

"For me, it's no big deal," said Valora, a 24-year-old husband and father of two girls. "It's what you train for."

But Valora admitted it's hard on his family. He was in Iraq when his second child was born in February.

"My wife knows," he said. "She knows that with the current tempo of the Marine Corps you are going to be going sooner or later."

Fighting in Afghanistan will be different than Iraq, largely because of the terrain and snowy mountain weather.

In Iraq, the Marines drove Humvees on highways, usually at breakneck speeds. Valora called it "Mad Max driving."

Roadside bombs were a constant danger and on two separate occasions they exploded beside vehicles in convoys he was leading, Valora said. No one was injured, but the tension it created typifies an Iraq deployment.

"I think Iraq was more mental," he said. "There was a lot more going on. Driving down the road, I was waiting for not what, but when."

But in Afghanistan, they will be driving up mountains on narrow donkey trails at speeds that make them a much easier target.

"I think in Afghanistan we will be worried a lot more with the weather and terrain and environment and they can engage us at farther distances," said Valora, who quit smoking in anticipation of living and working at up to 7,000 feet.

The Marines, who returned in April, have been eager to begin training again.

Sgt. Dustin P. Chamberlain, a 24-year-old section leader with a weapons company, said the Marines got a nice break after they returned, including a 30-day leave.

"But I still think a lot of us wanted to get back into training," Chamberlain said. "It's like a lot of things. If you don't do it, you get rusty. Everybody was anxious to get back at it."

Chamberlain said the Marines are trying to learn as much about the people and culture of Afghanistan as possible — and a few words in a native dialect.

"I can say stop and hello," he said. "That's all you need to say."

But some messages are easier to communicate, Valora said.

"You can point your weapon and they get the hint," he said. "International sign language."

In Iraq last November, the Marines were part of the battle for Fallujah. It was fierce, close-quarters, house-to-house fighting. For those who were there, the experience will help them survive in Afghanistan, Valora said.

But for those who were not, it is not an experience easily explained — to Marines, friends, or family, he said.

"When we went into Fallujah, we drove into the city and you heard bullets all around you," Valora said. "I thought, wow, here we go."

The Marines will deploy sometime in January or February.

Reach Mike Gordon at mgordon@honoluluadvertiser.com.