A head-on collision is the stuff of nightmares, and everyone worries about "that idiot" in the next lane who seems sure to cause an accident.

But when people die on the region's highways, most often it's in a single-vehicle crash.

Of the 7,945 people who died in the past five years in Virginia, Maryland and the District, 58.9 percent were in single-vehicle crashes.

"We are seeing a troubling trend: an epidemic of single-vehicle crashes . . . on area roads," said John B. Townsend II, a spokesman for AAA Mid-Atlantic. "In addition to operator error and unforgiving roads, certain risk factors -- such as driving at an excessive rate of speed, driving at night, driving under the influence and having a track record of prior traffic convictions and crashes -- are the leading common denominators."

Townsend reviewed National Highway Traffic Safety Administration statistics on fatal crashes between 2004 and 2008.

He determined that last year, almost 60 percent of the 1,449 people killed in the three jurisdictions died in single-vehicle crashes. They accounted for almost 64 percent of Virginia's traffic fatalities, 62 percent of the District's and 53 percent of those in Maryland.

In the area's most recent such crash, a Maryland woman died and a member of the U.S. national soccer team was injured on the George Washington Memorial Parkway on Tuesday. (For story, see Sports, D1.)

Although this year's statistics have not been compiled have recorded many single-vehicle deaths.

-- On Feb. 1, a 17-year-old passenger died when a vehicle struck a tree on Veirs Mill Road in Rockville.

-- In April, a 22-year-old Leesburg woman was killed when her car struck a tree on Gum Spring Road in the Chantilly area.

-- The driver of a sport-utility vehicle was killed in the District in May when he hit an electrical pole and a tree on Connecticut Avenue NW. Earlier in May, a 17-year-old driver was killed when he crashed into four cars on Seventh Street NW.

-- In July, a 44-year-old McLean man was killed after his vehicle left the road in Loudoun County, hit a tree and rolled over several times. The same day, a 22-year-old Potomac man was killed when his vehicle left the road and hit a tree on Bradley Boulevard in Bethesda.

-- An elderly couple died this month after their truck crossed two lanes and rolled over in a Rosemont cornfield off Route 17.

"Although most people think of single-vehicle crashes as freak accidents, there are many contributing factors," Townsend said. "Beyond a doubt, distracted driving is one of them."

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