The Battle for Route Irish. The ten kilometer road from Baghdad to the airport is often described as the deadliest in Iraq. The troops call it Route Irish, and it is a very important highway. It is the only good road from Baghdad to the airport, and is thus always full of traffic.
In practical terms, being the deadliest road means that it has, in the last six months, suffered one attack or hostile incident a day. About once every four days, a roadside bomb goes off along Route Irish. Most of the attacks or incidents do not result in any friendly casualties. For example, once or twice a week, a roadside bomb is found before it can detonate. That is considered a hostile incident. The road is heavily patrolled, both on the ground, and in the air with UAVs and helicopters. As a result, terrorists have to go to extraordinary lengths just to plant a roadside bomb on Route Irish. Terrorists have largely given up trying to sneak out at night to plant a roadside bomb on Route Irish, as they continue to do on thousands of kilometers of less heavily patrolled roads. In fact, most of the attacks on the road are from people in vehicles, or on the side of the road, firing AK-47s or RPGs at American vehicles, or tossing hand grenades. Sometimes a mortar will drop some shells on the road. These attacks often hit innocent civilians, which just adds to the unpopularity of the terrorists.
The most popular method of planting a roadside bomb is via the drop off. This is done by dressing up the bomb to look like trash, and then dropping it out of a moving vehicle. Often the bomb is triggered by a timer, that goes off soon after the bomb is dropped, preferably in the path of an American convoy. These bombs are not large, but if the aim and timing are right, American injuries can result. Again, the victims are often, instead, Iraqis who make up most of the road traffic. Another ploy that worked for a while was terrorists pretending to be doing road maintenance, but actually planting a remote control bomb. Patrols check the ID on road crews more frequently now.
Despite its reputation, you are still much more likely to be injured in a vehicle accident along Route Irish, than by a terrorist attack. Thats why Iraqi civilians continue to use the road so heavily. Most of the road traffic is civilians, and one attack a day is just considered another road hazardous on a road that would be dangerous even with out homicidal terrorists constantly trying to hit something.