Along the spine of Jutland runs a road. In places, it is paved, rolling easily over the hills and dales of the Danish peninsula. Along other stretches it is sand or gravel, winding through forests and across windswept moors. And in still other spots, it is simply an overgrown path, rocky and rutted, hiding in the woods and the wild grass.

Sometimes, it seems the world has passed this route by. But it was not always so. In fact, this road was once a vital highway -- and therein lies its tale.

Today, this route to the past, which tourists can follow by foot, bicycle and, in most places, car, is best known as Haervejen (pronounced Hairvine) -- or the Army Road -- since for millenia the way was one of clashing armies.

Running about 170 miles from Viborg in central Jutland south to the Eider River, about beyond the border in West Germany, Haervejen was the only land artery connecting much of northern Scandinavia with Continental Europe until alternate routes became available in the last few centuries. As such, it carried Danish armies marching against other Scandinavians; against mercenary Czechs, Poles and Spaniards; and, not surprisingly, against the neighboring Germans who, as recently as World War II, still were tramping over it.

But warriors were not the only ones to pass this way. Until 1870, cattlemen driving bullocks to market used it, so it was also called the Ox Road. During the Middle Ages, kings of Denmark were elected in Viborg and immediately afterward traversed it to the courts of southern Jutland. Thus, the road was dubbed the King's Way. And in 1150, an abbot in Iceland wrote a guidebook citing the route as part of the path the observant should take to Rome and Jerusalem. Hence, the name Pilgrim's Road.

Actually, Haervejen was not, strictly speaking, a road, but rather a thoroughfare sometimes more than 100 yards wide. In rough outline, it was laid down by the Ice Age's retreat, which left this high ground above flood level as both Jutland's watershed and a division between eastern Jutland's rich farmland and the poor, formerly unmanageable land of the west. Those utilizing it navigated by following hilltops or church towers; when the main route was in poor condition, they made sidetracks.

Before new road-building techniques superseded Haervejen's natural engineering, beggars and highwaymen, merchants and simple folk all joined the ongoing stream of humanity that flowed along this route, leaving for posterity traces of their passage. Along the way lie barrows and burial mounds, rune-stones and road markers, churches, inns and other sights and sites of long ago. Indeed, travelers who explore even fragments of Haervejen will find themselves not only on an excursion along the byways of Jutland, but also on a veritable treasure hunt into history.

Today, the official start of the road is marked in Viborg by a plaque in the pavement at the corner of Sct. Jorgensvej and Lille Sct. Mikkelsgade, across from the Sygehus Ost (East Hospital). The first traces of the road itself, however, are encountered at Rte. A13, since, for about 35 miles from there until a bit beyond Norre Snede, the modern highway follows the primary track of Haervejen with only minor deviations.

In Torning, a town just off A13, stands the red-roofed, whitewashed church where from 1819-1825 Steen Steensen Blicher was vicar. Blicher was also a poet and writer who drew upon his days here for inspiration. When Blicher lived, Haervejen still rose between the good lands and the bad. Though modern cultivation techniques have virtually erased the difference, a painting of Blicher standing on the open, seemingly endless, heather-covered moor evokes the previous landscape. Indeed, Blicher once wrote:

My home is in the russet heather land

My laughing childhood lit the moorland gloom . . .

Blicher memorabilia, as well as clothing and furniture from his time, are housed in a museum in the old vicarage opposite the Torning Church.

Also in this vicinity are traces of an old dirt byway of Haervejen, as it digressed from the main route to cross the earthen defense embankment along the Haller River. According to legend, this dike was used in 1157 when, on the wasteland called Grathe Moor, the Danish king Svend was defeated by Valdemar the Great, who then succeeded him. A slim stone monument commemorates the battle.

Another sidetrack here -- in parts so narrow and sunken below field level that opening a car door is impossible -- leads toward the Funder Kirkeby area where a 2,000-year-old human relic was discovered 35 years ago. Some land here is boggy and known for excellent peat. In 1950, two brothers cutting peat among the low bushes and brush unearthed an almost perfectly preserved Iron Age body. It has been called Tollund Man and its small leather-capped head -- with a rope around its neck -- lies in the Silkeborg Museum, about seven miles east of the bog.

Near a busy crossroads farther south on the Haervejen stands the 12th-century church at Norre Snede, one of numerous churches built between 1100 and 1250, the early days of Danish Christianity. This church boasts a rose granite, Romanesque baptismal font featuring two lions chiseled in high relief that has been exhibited in England and the United States. A mound behind the church is said to be a king's grave.

Just outside Norre Snede, at Ballesbaekgaard on the edge of Rorbaek Lake, is a mini-museum devoted to Haervejen. It displays maps, photographs and a historical chronology, as well as Stone Age implements found along the road -- among them a flintstone ax, arrowheads and a dagger.

Slightly south of Norre Snede, however, off A13, is Hundshoved -- or Dog's Head -- and both a road sign and a placard announcing "Haervejen" itself. The eight or so miles of the old road from Hundshoved via Kollemorten to Harreso comprise the longest continual stretch extant of the original. Though now of brown dirt and stone, Haervejen is easily traversible here as it winds through fields of bluebells, daisies and heather; past red and yellow farmhouses; among towering oaks and pines. Edging the roadside are grass-and-flower-covered mounds -- graves of anonymous fallen travelers.

On protected park land in this vicinity, at Tinnet Krat, are the sources of two large Danish rivers, the Gudenaa and the Skjern. Oozing from the earth in the woods, the two, though not far apart, run in opposite directions, one to the east and one to the west -- Denmark's "Continental Divide." Also nearby are the grass-covered earthen fortification, the Margrethe Dike, and Oster Nykirke, a white-stucco and gray-stone medieval church with an impressive Renaissance altarpiece. Because the church stands on a 426-foot hill -- which is high for Denmark -- when the minister ascends the pulpit, he is said to be the highest man in the country. Once used as a sea marker, the church's great bronze candlesticks reputedly were given by a grateful sailor.

The present also intrudes: From here can be spotted, on a nearby hill, a NATO radar installation. Also in this area are two attractions of particular interest to children -- Lions' Park, a drive-through wild animal preserve at Givskud, and Legoland, the miniature community built of Lego blocks at Billund.

The past is rejoined, however, at Harreso, where a decent steak is served at the 350-year-old kro, or inn, that was a post stop when, beginning in the 17th century, Haervejen was used as a post road. Proprietor Kristiansen is knowledgeable about the road, which here offers two short detours.

One detour, to the east, rejoins Haervejen above Norup. The second small branch of the main road leads to Jelling, with its mammoth Viking burial mounds and massive rune-stones. The grassy mounds -- the larger of which is about 50 steps high -- are believed to have been the tombs of Denmark's last pagan royalty, the Viking Queen Thyra, who died around 935 A.D., and her husband, King Gorm. Lines of big stones between the mounds form a portion of the ship's outline often found at Viking gravesites.

But the most significant stones here -- indeed, among the most significant in Scandinavia -- are the two hunks of granite carved with 1,000-year-old texts. The smaller stone was erected by Gorm in honor of Thyra. The larger, put up by the couple's son, Harald Bluetooth, around 980, declares that Harald "made the Danes Christians." Though a heathen figure appears on the stone, there is also what is believed to be the oldest known depiction of Christ in Scandinavia. Thus, this stone has been dubbed the "birth certificate of modern Denmark."

From Jelling to Vojens, Haervejen is mostly a paved rural highway, occasionally a stretch of hard-packed dirt. It runs through small, dense forests, past little thatched-roof houses and over heathland brightened by wildflowers. From Norup Church there is a view of Engelsholm Castle. In a meadow of bluebells near Randbol, there is a rune-stone called "Store Rygbjergsten," erected by a royal sheriff for his fiance' who died before they could be married. Because of the loving message on the stone, some call the sheriff Denmark's first romantic poet.

Along the way to Klebaek on an August afternoon, a troop of boy and girl scouts may be seen pushing covered wooden carts carrying camping equipment as they head toward what they say is one of the best Viking burial sites around. When they reach the barrow of King Legom, they scamper up, then play tag around the menhirs -- upright monumental stones -- that punctuate the area. Like many other young Danes, they are spending several days hiking a length of Haervejen. (A full-scale, week-long march along the entire length of the road is organized the first weekend in July for all who wish to participate.)

Just south of Vejen, where a castle once stood, the road crosses the Kongeaa -- or King's River -- which, between 1864 and 1920, was the border between Denmark and Prussia. In 1920, the northern part of the province of Schleswig became part of Denmark. From here on, through North Schleswig, Haervejen plays hide-and-seek. It crosses and crisscrosses the paved route at random, running in spots along the edge of pastureland, in other places bumping through weed jungles.

At Immervad and Gejlaa stand 18th-century stone bridges. In a clearing in the woods near Urnehoved is an old court area where, on semi-buried stones, important dates from the 12th century on have been noted. And in the brush on the other side of the road stands a monument engraved with a rider on horseback receiving a drink. Here once stood the Bommerlund Inn, famed for its special schnapps. (The innkeeper was German, and when the northern part of Schleswig became Danish in 1920, he moved to Flensburg where he continued to produce the Bommerlunder schnapps -- now a product of West Germany.)

The road continues on across the border about 35 miles into Germany, where it ends. But this is as good a moment as any to head for refreshment -- perhaps that special schnapps -- and for reflection.

For centuries, Haervejen has proved a resilient byway. And it remains a prod to the imagination, a pastoral link to eras gone by. Phyllis Ellen Funke is a free-lance writer.