One may travel to the ends of the earth in search of exotic scenery and breathtaking views, but few global glories offer the variety, uniqueness or sweeping majesty of the remarkable treasure locked within the heart of our continent: the Great Lakes of North America.

This extraordinary freshwater sea, spanning five separate lakes and joining two mighty democracies across the world's longest unguarded border, transforms the interior of the nation. A place of rivers, prairies and plains, the American heartland also includes astonishing canvases that seemingly could only have come straight from Winslow Homer's studio on the coast of Maine: vistas of sandy beaches, craggy inlets, gritty harbors, sun-bleached lighthouses, crashing waves, shimmering seas, great ships and colorful sails, and over it all, troops of raucous gulls.

To accentuate the splendors of this surprising maritime reality, lively cities stand along the lakes, bringing unusual ethnic diversity to the entire region. The aromatic foods and colorful garb of such far-away peoples as Thais, Filipinos, Indians, Arabs, Poles and Greeks can be found in brilliant strokes around the shores, lightening the seemingly dominant hues of farm-belt green and rust-bowl umber.

Stretching almost 700 miles from north to south, and nearly 900 miles from east to west, the lakes and the country around them offer travelers -- be they harried businessfolk or vacationers looking for leisure -- superb opportunities for exploring places that refresh the spirit and broaden the mind. Traveling eastward in the same direction that water flows through the vast system, the five lakes are: Superior, Michigan, Huron, Erie and Ontario.

Although exceeded in total volume by the Soviet Union's mile-deep Lake Baykal in central Siberia, the Great Lakes at 94,500 square miles are the largest expanse of fresh water on the globe.

Ancestral home to many of the continent's northern and eastern Indian tribes before the arrival of white men, the lakes ever since have played a special role in the development of Canada and the United States. Moving up the St. Lawrence River in the 17th century, English and French explorers, trappers and priests first claimed the lakes (naming four of them after the Indians they shoved to the brink of extinction), then fought over them. Historic sites of battles, forts, skirmishes and Indian communities abound.

When peace finally reigned in northern North America after the War of 1812, farmers and industrialists arrived. Together, they stamped the lakes with commerce and abundant agriculture. And from Buffalo to Chicago, they erected in the next 100 years what even today remains the greatest complex of manufacturing and transportation facilities ever assembled on earth.

Smokestack America has been weakened by the troubles of the 1980s, but its raw industrial strength remains a powerful force in the world. Indeed, for nearly three decades, the St. Lawrence Seaway's locks and canals have given the world's ships direct access to this empire. It is not uncommon to see the flags of European nations who once fought for control of the lakes moving peacefully across the heartland landscape, borne on the masts of salty steamers.

A gift to the continent from the Fourth Ice Age, each lake has its own special character, imparted by the glaciers.

*Lake Superior. The largest of the five, and the least tamed, is Superior, which also happens to be the deepest, at 487 feet mean depth. Like all the lakes, Superior offers extraordinarily diverse travel opportunities. For those seeking solitude, or camping adventure in the legendary Great North Woods, the upper reaches of Superior are home to moose, bear and eagles along the remote northern and western shores.

But it also remains one of the nation's busiest waterways, shipping grain from the Northern Plains states to tables and stables worldwide and taconite iron ore pellets to the struggling steel mills of Indiana, Ohio and Pennsylvania.

While pollution from the iron mines of Minnesota reached alarming levels in the 1960s, major cleanups have improved water quality so that its tasty big-game fish -- lake trout, whitefish and coho salmon -- are considered safely edible, improving cuisine throughout the region.

This mightiest of the lakes also offers the charms of such regional American cities as Duluth, Minn., and Superior, Wisc., at its western tip; to Sault Ste. Marie at the eastern outlet. Hundreds of grain and ore carriers dock at the Duluth and Superior ports every year, and Duluth's ambitious downtown renewal effort has brought a new sparkle to the community.

One of America's most scenic drives is the North Shore Drive, running 150 miles from Duluth, north and east to the Canadian border. The area is little changed from the days of the voyageurs; there is ample opportunity in the nearby Boundary Waters Canoe Area to use the same means of travel -- canoe.

*Lake Michigan, the only lake wholly within U.S. territory, is distinguished by its beautiful expanses of sandy beach and dune; the lush farmland and vacation areas of the Michigan peninsula to the east and the Wisconsin shoreline to the west; and the presence of Chicago, undisputed queen city of the Great Lakes, at its southern end. Like a tiara, the graceful gossamer of the Mackinac Bridge spans the lake's northern outlet into adjoining Huron. A drive across this suspension bridge at dawn easily compares to sunset bestride the Golden Gate.

*Lake Huron's contribution to travel rests on its numerous shoreline fishing camps, and the ringside seats it offers along the St. Marys River leading to the world-famed locks at Sault Ste. Marie, Mich. Despite a sharp decline in voyages by Great Lakes ore boats, the "Soo" locks remain the best place in the country to watch these distinctive vessels, their pilothouses perched right up over the vertical bows, do their vital work.

*Lake Erie. Declared biologically "dead" 25 years ago, Lake Erie (the shallowest at 87 feet mean depth) has struggled back to life. Sport fishing is stubbornly returning, and Cleveland, where the Cuyahoga River once caught fire, is in the midst of an urban renaissance that has captured the nation's attention.

Standing with Cleveland along Erie's south shore are other gritty industrial complexes: Toledo and Sandusky, Ohio; Erie, Pa.; Lackawanna and Buffalo, N.Y. But there also are miles of serene farmland on either shore, peaceful lakefront and some of the best smallmouth bass fishing anywhere in the Great Lakes.

American history buffs will find rewarding a special visit by ferry boat to the small community of Put-in-Bay, on South Bass Island just north of Sandusky. This is the site from which Oliver Hazard Perry sallied forth in his flagship, Niagara, and defeated the British in the Battle of Lake Erie during the War of 1812. Perry's famous victory message, "We have met the enemy and they are ours," was engraved in the nation's chronicles long before Walt Kelly's Pogo offered a latter-day version: "We have met the enemy and they are us."

*Lake Ontario. Finally, there is Ontario, easternmost of the five, which seems, by its combination of sophisticated cities and superb recreation areas, an amalgam of the other four.

Any talk of Ontario must include Niagara Falls, one of the continent's most beloved, most visited and mightiest natural wonders. Located north of Buffalo, between Erie and Ontario, the falls are nothing less than astonishing in their power and glory.

Eastward along Ontario's shores lies some of the most bountiful farmland in either Canada or the U.S. At harvest time, the apples and garden vegetables along the roadside are glories of their own. And fishing, boating and camping are available along both shores much of the year.

While they border some of the wildest and most remote parts of the country, the Great Lakes are host to many of the continent's most important cities. From Toronto, the suave giant of Canada on the northern shore of Lake Ontario, to renascent Cleveland across Lake Erie, to Chicago, queen metropolis of the region; from squeaky clean Milwaukee, to perennially troubled Detroit, the lakes cities offer special attractions of culture, cuisine and history.

In all, more than 37 million Americans and Canadians live within the immediate region. In this huge population, constellations of most of the world's ethnic groups have found new homes. Chicago, Milwaukee, Gary, Detroit, Toledo, Toronto, Buffalo -- each boasts its special populations. Even a small place like Racine, Wisc. (pop. 85,000), just north of the Illinois line, harbors its own distinctive ethnic group -- the Danes. As everywhere else in the region, life has been enriched by the distinctive, proud presence of a self-aware nationality. The Racine kringle, with morning coffee, puts the pastries of the world on notice.

The unifying presence in all this diversity, however, is the huge inland sea itself. The five Great Lakes offer endless variations on themes of seafaring and surf watching that have excited and consoled us since the human chronicle began. Wonder of wonders, they are within easy, economical reach of all Americans.