There is something forbidding about England's Cornish coast, something massive and lonely, even prehistoric, the rough-hewn work of some vastly powerful sculptor who heaved up great black, jutting cliffs of granite, spilling their jagged edges into the sea and flinging smaller chunks beyond the coastline to form bare, misshapen islands just offshore. D.H. Lawrence thought the Cornish rocks were "primeval . . . like the original darkness."

So walking the country's formidable southwest peninsula involves the sense of going backward in time, a welcome respite from modern stress and congestion and the massed uniformity of urban skylines, though the quiet civilization of a village pub is seldom more than a mile or two away.

For four days last May, a very small band of Washingtonians hiked the Cornish coast between St. Ives on the west and Coverack on the east, walking in all about 38 miles and sharing the mystical, brooding vistas, the bursts of heather and wildflower, the brisk offshore wind from the north, and the pleasure and pain of pure physical fatigue.

The three of us hotel, the Tregenna Castle in St. Ives, and motored out each morning to the starting point of our hike in a small van, returning in the late afternoon for long immersion in hot tubs, followed by drinks and an 8 o'clock dinner. As after a hard day on the ski slopes, we went to bed early, and sleep came swiftly .

In a brief introduction mailed to us before we left Washington, our guide advised that the weather in Cornwall "is largely unpredictable and varies wildly." Daphne du Maurier, who has celebrated her native Cornwall in mellifluous novels of dark intrigue amd adventure, is a bit more eloquent. The peninsula, she has written, is "bathed in a kind of perpetual spring," but she attaches caveats. Spring (even summer) in Cornwall is not like spring in Washington, but more like "a mild February that has prolonged itself into a damp June." Rain falls in a "mizzle"; eccentric patches of white mist shroud one village while leaving the next two in sunlight; fierce winds blow from the sea, carrying salt spray 10 miles inland and bending trees. slightly menacing tones of a Marine Corps drill instructor, "The walks take place regardless of the weather, so be prepared for extremes."

Predictably we overreacted, packing extra woolens, thermal underwear, even ski jackets. The temperature during our sojourn averaged about 50 degrees, with a moderate to brisk offshore wind blowing steadily; the sky was overcast most of the time, but it did not rain, and for one whole day the sun shone brightly, etching the cliff faces in pure light and flicking a thousand diamonds on the shimmering sea. We quickly learned what experienced hikers already knew: that walking generates body heat. You don't need wool trousers, wool hats, gloves or a jacket, except in extreme cold. So we shed clothing experimentally that first morning and gradually arrived at a practical accommodation with the elements: thermal undershirt, turtleneck, light sweater and khaki trousers; and sturdy hiking boots were a must.

That first day took us eastward from Lizard Point past the main Cornish lighthouse (whose construction was long resisted by native mariners who profited from shipwrecks), past a collapsed cave of malevolent black ashy fragments called the Devil's Frying Pan, past black-and-white cows grazing in thick grass of deepest green, over wooden stiles, down ravines and up the other side, following the jagged contours of the coastline.

After a challenging four miles, we rewarded ourselves with a lunch of salad, cheese and beer in Cadgwith. Also that first morning we crossed Pistol Meadow where in the mid-18th century a ship was wrecked and more than 100 corpses washed ashore in the stony cove beneath the cliff, jammed into rock crevices and tangled in seaweed together with an astonishing quantity of firearms, mostly pistols. The superstitious locals found the bodies there and, knowing that unburied sailors give off flickering corpse-lights in the night and restlessly haunt the scene of death forever, they undertook the gruesome task of dragging them up the cliff and burying them all in large pits on the high pasture -- known thereafter as Pistol Meadow.

We proceeded farther eastward in the afternoon for another six miles through a tangled profusion of gorse bushes and sea-toughened trees to the village of Coverack.

We walked for five hours in all and covered slightly more than 10 miles -- not a great distance, but long enough for the first day. After about four hours my legs lost their elasticity, which made the last hour moderately uncomfortable and the final 15 minutes nearly painful. (The second day -- when we walked in the opposite direction from the same starting point -- was the toughest physically, not because of the terrain, which flattened out after a steep beginning, but because our legs were tight from the exertion of the day before. Fortunately, as happens in basic infantry training, we became steadily hardened to the trail, our legs and related parts growing stronger with each passing day. The fourth day was the easiest physically, with energy and resilience on the rise, but then, alas, the enterprise was almost over.)

Our first day's walk was somewhat foreshortened by an early-morning visit to a unique Cornish landmark, St. Michael's Mount, the smaller English cousin of the more famous Mont St. Michel that lies across the channel on the Norman coast. Both were built as church fortresses surrounded by water at high tide.

St. Michael's Mount is a quarter mile offshore in Mount's Bay opposite the trading town of Marazion, a few miles east of Penzance, and we were privileged to have a private tour conducted by the resident heir, the Lord Levan, a former London barrister. The English castle is much smaller than its French counterpart, and was historically far less a bastion of the church. Mont St. Michel was a religious center and monastery with a sprawling town within its steep and winding streets. St. Michael's Mount was always primarily a fortified residence with a chapel, the home and power seat of moderately important southern nobility who frequently opposed the reigning monarch in London.

It is a magnificent sight, rising massively out of the bay on a cold gray morning. We toured its high defensible ramparts, its gun rooms and council chambers and its chapel, and came at last to the comfortable apartment inhabited by the lord and his wife. They told were enjoying the early spring quiet, while preparing for August, when they receive up to 3,000 visitors every day.

The second day, walking westward from Lizard Point, we explored a small stone church, established by a Breton cleric about 300 years ago and unusually placed right on the beach beyond Mullion Cove.

Proceeding in the same direction, we climbed a high bluff and 30 minutes later descended steeply to one of Cornwall's rarest vistas. Called Loe Bar, it is a long, wide stretch of coarse beach, a humped ridge of sand separating the sea on the left from the darker, stiller waters of an inland lake, edged by heavy woods, on the right. In summer, our guide told us, Loe Bar is a picnic site for thousands; in winter, when the lake is swollen by streams from the north, it overflows and runs across the bar to meet the sea.

The third day was memorable for a scene at the Tinners Arms Public House in Zennor, a tiny village southwest of St. Ives. Zennor is an area where tin mining once flourished, but all that now remains is ruins of a few stone mine shafts overgrown with gorse bushes, presenting lonely, broken silhouettes against the sea.

We arrived at noon on Sunday, just as the morning service at the stone church beside the pub was ending. We were eager to look inside, as it is known as a classic of its kind, with a rare stained-glass window facing south and the legend of a local mermaid carved on the pew ends. But the church was filled to overflowing and the atmosphere seemed unusually intense, so we decided not to intrude.

When the doors opened a few minutes later, the entire congregation flowed into the Tinners Arms to continue in more secular form their observance of V-E Day. Veterans of the Battle of Britain and the Normandy landing stood in dark suits and blue blazers with splendid arrays of World War II medals. brance, part somber recollection, part joyful celebration of Britain's "finest hour."

Then onto the coastal path again for a seven-mile walk northwestward to St. Ives. Exhilarated by a bright sun and a brisk wind and confident of our new-found stamina, we hummed along. At 5 o'clock we marched into St. Ives with the measured swagger of a very small triumphant army, seeking in the narrow streets, and finding, a proper Cream Tea, which in Cornwall means tea with scones, strawberry jam and the famous Cornish clotted cream.

The fourth and final day took us south from Sennen on the west coast to Land's End, then eastward to Porthcurno for lunch. Rain threatened and the forbidding rocks of Land's End were curtained in gray mist, but there was no precipitation, not even a "mizzle."

At Porthcurno the path descends steeply to a rough shell-strewn beach, and there we stopped at a tidy pub-hotel. The tourist season being still a month away, the place was deserted, but we lunched splendidly on vegetable pie, salad, trifle, tea and beer. Also on the cliffs near Porthcurno, we looked in on the Minack Theatre.

A remarkable open-air affair carved into the rocks high above the open sea, it offers summer plays ranging from Shakespeare to comic opera and claims never to have canceled a performance on account of the weather. According to local scribes, the Minack players have shouted their lines into the teeth of an Atlantic gale while being pelted by driving rain, all for the benefit of four intrepid souls in the audience doggedly hunkered down on their stone benches.

About three miles farther east, at Penberth Cove, a charming narrow opening in the cliffs where a clean fresh-water stream runs into the sea beside a huddle of small cottages, we declared a happy ending. That evening, after a long, rewarding soak in our tubs, we ordered champagne in celebration of an experience that had satisfied both our esthetic and physical senses.