ROLLING NORTH ON INTERSTATE 95, MAY 31 -- The Oak Ridge Boys are singing "Bobbie Sue" on the stereo, the air-conditioned cabin is crisp and cool, and driver Jack Kochiss is pushing his big Kenworth 444-horsepower tractor-trailer through the sandy pine woodlands of North Carolina at a steady 65 mph. He's got a state trooper escort ahead, a couple of backup trucks behind and -- for cargo -- a single, authentic, original calfskin copy of a medieval document known as the Magna Carta.

Seven hundred seventy-two years ago this June 19, in a meadow at a place called Runnymede in England, King John was forced by his rebellious barons to place his seal upon this very document and 10 other copies of it. His act, in the year 1215, guaranteed that life, liberty and property were rights not to be taken without due process of "the law of the land," and established the principle that even a king is subject to a higher law.

Today these ideas, through our Constitution with its Bill of Rights, are part of the glue of American political consciousness -- as familiar to us as an 18-wheeler thrumming up the interstate.

In King John's time, the original copies of the Magna Carta were taken to the English counties and towns to be read to the populace. Now Kochiss, 47, an independent trucker out of Fairfield, Conn., is bringing this document -- the best preserved of the four remaining copies -- to Washington as part of the bicentennial celebration of the American Constitution.

"It's a part of everybody," he says. "It's your history and how your country was put together. To me, it's amazing that it's so old and yet so well preserved. It's still here!"

The Magna Carta (Latin for "Great Charter") will be on view, starting at 9 a.m., on Monday and Tuesday, then again Thursday and Friday, in this red-white-and-blue display truck, which will be parked on the Mall at Third Street and Jefferson Drive SW, just east of the Air and Space Museum. On Wednesday it will be parked near south side Corridor 3 of the Pentagon. Admission is free.

Also aboard the truck and open to view is an original draft of the Constitution, a copy of the Bill of Rights signed by Thomas Jefferson, one of the original copies of the Declaration of Independence and other historical documents and artifacts.

"It's the only time all these documents have been assembled in one place," says security chief Don Munson. "It's pretty dynamite."

Yet somehow it is the Magna Carta itself -- perhaps because it is so ancient, so fundamental, so irreplaceable -- that captures the imagination.

To Munson, a retired lieutenant colonel who once ran the Army's airborne training school at Fort Benning, the document is "Maggie," and his eyes shine as he speaks of her.

"Oh, there's not much to see," he says, slyly dissembling. "It's a dusty old document. It's got the stains and the tears of years on it."

This 18-wheel rolling museum has been on the road three months now, crossing America with Kochiss at the wheel, Munson riding shotgun, Tom Frazier and Ernie Silva doing advance work and Jeff Moore driving one of the backup trucks. American Express is footing the bill to the tune of $1.5 million, and two agencies -- the U.S. Constitution Council of the 13 Original States and the Bicentennial Commission of the U.S. Constitution -- are providing official backing.

Even with all this support, it was a struggle to get the project going. When the artist came to paint the big brown eagle and patriotic motif on the sides of the truck, Munson recalls with a laugh, "he misspelled the word 'Constitution.' "

Also, American Express was "very particular" about the colors being just right; the blue had to be blue-blue, and "we had to try four different colors of red."

But the result is a spectacularly handsome truck.

At a layover last night at Fort Bragg in Fayetteville, N.C., Kochiss -- even though no one had eaten for 12 hours that day -- spent more than an hour meticulously washing the truck for its appearance in Washington.

"It's like his own kid," says team member Frazier, a 28-year-old political junkie who is between campaigns right now. "He takes a lot of pride in it."

The Magna Carta was in Washington March 11, but only for for a White House ribbon-cutting to open the "Roads to Liberty" exhibit. Since then it has toured Chicago and other Midwest cities, then headed for Texas and Florida.

Kochiss and the others work long hours, but say they have relished the experience. They remember the stunning beauty of the Alamo in San Antonio at dusk, with their truck parked outside; breakfast at a topless doughnut shop in Fort Lauderdale, Fla.; the crowds of enthusiastic people who waited three and four hours in line in some places to see the exhibits.

There was the time former chief justice Warren Burger, head of the Bicentennial Commission, came up to Stratford, Conn., to see the truck being refurbished.

"He brags to everybody about this project," says Kochiss.

Another time, Kochiss gave a ride in the truck to the Very Rev. Oliver Fiennes, dean of Lincoln Cathedral in England, where this copy of the Magna Carta has been kept since 1215. Kochiss found Fiennes "a great guy, very down to earth."

Security, Munson says, is a major consideration since the documents are priceless. State and local police and the military have provided escorts and guards all across the country, day and night.

"We've had just fantastic security coverage," Munson says. "When we drove through downtown Baton Rouge, God Almighty and Huey Long couldn't have done better."

In three cases, he says with the satisfied air of a retired paratrooper, "We had air cap."

The troopers seem to enjoy the escort duty and consider it significant. Sgt. Clement Price of the North Carolina Highway Patrol seemed excited to be guarding the Magna Carta and a copy of the Constitution, and he took the opportunity to voice a familiar lawman's complaint to a reporter.

"The people who wrote the Constitution," according to Price, would never have wanted "the courts {to be} so full because the attorneys have taken the Constitution and turned it all around with all these little stipulations."

As the caravan rolled into Virginia this afternoon, Munson, following in one of the backup trucks, got on the CB with a female state trooper.

"When we were in Minnesota," he told her, "they called the female troopers she-bears and honey bears. What's your handle?"

"She-bear and honey bear, 10-4," she answered.

Munson, who was wearing a cowboy hat, shades and a snakeskin belt with a buckle fashioned from four ounces of 24-karat gold, says there was a security scare at a university city in the Midwest when a bearded, unkempt man in a ratty Army jacket seemed to be paying overly close attention to the documents.

As the man approached the Magna Carta, "the guard was about to jump him, but didn't. It's a good thing, because he turned out to be the chairman of the history department at the university."

The Magna Carta is kept in an oak display case inside the trailer portion of the truck. The temperature is held at between 50 and 70 degrees. A device sounds an alarm if the ancient parchment is being exposed to more light than it can healthily handle.

When it goes off, Munson says, "I'll immediately cover the document. We keep a red velvet cloth close at hand." Usually there was no real problem -- sometimes it's just that "an aluminum ramp will pick up the setting sun" and reflect it inside for a moment.

As you approach the Magna Carta, you see, as Munson puts it, that "she sits up there rather regally" -- a gray parchment about half the size of a newspaper page, bearing 5,000 Latin words written in a small, neat script.

Maybe if you were a scholar, you could read it.

"The Magna Carta is perhaps the single most important building block of modern democratic government," says a plaque above the document.

"The importance of the Great Charter to posterity," writes Maurice Ashley in "Great Britain to 1688: A Modern History," "was that it enshrined, in however crude a manner, the mighty principle of the rule of law: it suggested that monarchical government should not and need not be arbitrary, that it could be subjected to limitations more precise than the vague laws of Edward the Confessor or even the coronation oath of Henry I; it demanded the consent of those concerned to exceptional taxation; it required that the king should seek the advice of his natural counselors; it recognized that every section of the community that claimed to be free possessed its own prescribed liberties or privileges."

At Fort Bragg, several airborne rangers with their maroon berets, jungle fatigues and spit-shined boot tips were assigned to guard the truck overnight. They seemed ecstatic to be given a quickie tour of the exhibits; they also seemed somewhat more interested in the Constitution than in the Magna Carta.

Second Lt. Michael Marquette, 26, of Mystic, Conn., who was in charge of the detachment, mused quietly: "My first night on duty and I'm guarding the Constitution. Outstanding."

The caravan crossed the 14th Street Bridge at 5:55 p.m. There was a foggy mist over the river, diffusing the light of the afternoon sun.

A U.S. Park Police cruiser, red and blue lights flashing, led the way to the exhibit site on the Mall.

Kochiss eased the truck past the Air and Space Museum, looking around at the government buildings, the Mall, the relaxed tourists eyeing the truck.

"Not bad," said Kochiss. "Not bad at all."