A long line of nearly 100 vehicles stretched out along the White House Ellipse on the morning of July 7, 1919, replete with heavy troop carriers, light trucks, sidecar motorcycles, reconnaissance cars, field kitchens, blacksmith shops and one Renault light tank.

The automobiles were a cross section of the vast motor pool acquired by the federal government during World War I. Though an armistice had brought peace to Europe the previous year, the military had given itself a new mission: driving a convoy across the country. Flush with surplus Army vehicles, the War Department intended to send a first-of-its-kind motorized expedition from the District to San Francisco.

“This is the beginning of a new era,” Secretary of War Newton D. Baker read into an amplifying horn before a crowd estimated at 8,000. “This World War was a war of motor transport; it was a war of movement.”

As the Associated Press would write, the notion was “to develop a through route from coast to coast for motor transport and demonstrate the practicability of long distance commercial transportation by motor trucks.”

Baker predicted that the convoy, navigating the thousands of miles of unpaved back roads, would reach California by early September.

To mark the significance of the undertaking, Baker unveiled a monument at 10 a.m. beside the White House fence line. The “Zero Milestone” was equal parts historical marker and furtive public relations stunt, paid for by the National Highway Marking Association. The auto lobby hoped a transcontinental convoy would grease the wheels for increases in highway appropriations and drive profits for the sign-making industry.

Draping the occasion in rhetorical grandeur, The Washington Post explained that “the monument is designed to be the milestone from which, as from the golden milestone in the Forum at Rome, all road distances will be reckoned.”

The Army’s road trip got off to a rocky start, with several vehicles breaking down that afternoon on the hilly roads leading out of the District. The party made camp the first night in Frederick, Md., where a brevet lieutenant colonel joined the group as a last-minute observer for the Tank Corps. Dwight D. Eisenhower, then 28, was there “partly for a lark and partly to learn,” he wrote later, because “nothing of the sort had ever been attempted.”

In the weeks ahead, engine troubles plagued the convoy, which progressed at an average pace of less than 6 mph. Still, the expedition continued to attract national attention, and large crowds regularly turned out in town squares as the convoy worked its way west. In Pennsylvania, newspapers reported that the vehicles were greeted by “a large delegation of State and city officials to accompany the convoy into Gettysburg.” State police escorted the convoy across Ohio, and politicians in Iowa opened their dining rooms to the traveling soldiers.

Road conditions worsened as the Midwest gave way to plains country, where summer heat baked the earth dusty, and the sand clogged lungs and engines. On Aug. 2, the convoy’s daily log recorded a thunderstorm that sent 25 trucks sliding off the muddy right of way. Each had to be dragged out by the party’s ever-useful salvage tractor. The next week, another truck burst into flames because of a “carelessly tossed” cigarette butt.

Some of the chaos was deliberately engineered mischief. One evening in Wyoming, Eisenhower convinced the soldiers that their camp was vulnerable to attack by Native American warriors.

“Sentinels were posted that evening,” according to one biographer, “while Ike and his friend took concealed positions outside the perimeter and exchanged warrior yelps in the best tradition of the Old West.” After an overeager soldier discharged his weapon, a report of “hostile Indians” was dispatched to the War Department, before Eisenhower intercepted the messenger “faster than any vehicle in the convoy.”

The motorists slogged on across the Rockies through narrow mountain passes and steep switchbacks. Several stops were made in salute to the distant Zero Milestone, such as in Ogden, Utah, where a highway marker was left behind to inform motorists of the 2,208-mile distance to Washington.

On Sept. 6, 1919, the vehicles limped into San Francisco, where the daily log appreciatively noted “fair and warm” weather and fine “paved city streets.” Twenty-one of the doughboys had suffered injuries or fallen sick over the course of the journey. The heavy vehicles had damaged or destroyed 88 bridges and caused 230 road accidents. One Army captain described the weeks on the road as “comparable to those generally experienced in the advance zone of battle operations.” (This was coming from a World War I combat veteran, no less.) All of the convoy participants who reached the end were slated to receive medals for their tour of duty.

Making their way up Market Street in San Francisco, a parade of mounted police officers leading the way, the procession was bombarded with flowers by low-flying Army and Navy airplanes. Another milestone was dedicated at the Presidio to mark the end of the journey.

In his final report to the chief of the Motor Transport Corps, Eisenhower reflected that “extended trips by trucks through the middle western part of the United States are impracticable until the roads are improved.” Years later, he would see the possibilities of a national highway building program firsthand while leading mechanized Army forces on the autobahns of Nazi Germany.

“The old convoy had started me thinking about good, two-lane highways,” Eisenhower wrote, “but Germany had made me see the wisdom of broader ribbons across the land.”

As president, Eisenhower would sign the National Interstate and Defense Highways Act, which allowed for the construction of 41,000 miles of broad roadways. Though a numbering system based on Washington’s Zero Milestone failed to gain traction, a squat granite milestone remains on the Ellipse a century later.

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