THAT INFAMOUS AIRPORT ROAD.

The airport, closed to commercial traffic since the war, houses the offices of the U.S. military's top commanders, who often travel down the road to Baghdad for meetings with the U.S. civilians overseeing the occupation of Iraq. When the airport reopens to commercial flights, the road will be a vital link in the rebuilding of Iraq; its safety will be crucial for merchants, contractors, diplomats, humanitarian relief officials and others.

A senior military official said U.S. forces were "paying special attention" to the road because of its significance and had sharply increased security there. "It's a very important route," he said. "Given the amount of military traffic on the road, it's an obvious target."

The task of securing the road has fallen to the 1457th Engineer Battalion, a National Guard unit based in American Fork, Utah. Four companies of engineers and heavy equipment -- bulldozers, front-end loaders and dump trucks -- arrived here at the end of May.

They have worked to secure the roadsides and the median strip, which are both wide and thick with trees and bushes. They have filled in trenches, destroyed abandoned guardhouses, cleared and burned thick brush and removed unexploded ordnance and land mines -- some newly planted to kill U.S. forces, some dating back decades.

Read about the National Guardsmen tasked to clear and defend that road here.