Vancouver Island's West Coast Trail is one of the rawest, most rugged and most extravagantly beautiful hiking experiences in North America.

It's a hike that has everything: sea lions, sea otters and bald eagles; a trail that switches back and forth between log-jammed rain forest and tidal shelves dominated by jutting headlands; lighthouses, Indian ferrymen, petroglyphs; foggy nights punctuated by moaning foghorns; brilliant days of beach hiking. And it also has ropes, cable cars, ladders, suspension bridges, boardwalks and logwalks spanning otherwise impassable gaps and barriers.

In 1972, the 48-mile route (also known as the Lifesaving Trail) was made part of Canada's Pacific Rim National Park, which was then being formed. After several million dollars of upgrading, the trail has since become a formidable challenge for backpackers and naturalists.

We had been considering the trip for almost a year, our enthusiasm tempered by such mixed endorsements as the Sierra Club guidebook's comment: "50 miles of the most spectacular, demanding hiking on the continent." A final burst of hot-and-cold superlatives from friends in Seattle last summer decided it: We would find out the truth for ourselves.

As it turned out, the advance descriptions paled when compared with reality. Both of us are experienced hikers, but we were not prepared for the magnitude of rewards and punishments we encountered hiking the West Coast Trail.

Known as the "Graveyard of the Pacific," the southwest coast of Vancouver Island has claimed more than 200 ships over the centuries. The area is a windy stretch of capes and shoals opposite Washington's Olympic Peninsula, and the victims of shipwrecks often died trying to scale the steep cliffs and penetrate the dense forest. In 1906 the S.S. Valencia wrecked off t his coast, and 126 passengers and crew members perished when rescuers failed to reach the sinking ship. The outcry following that disaster spurred the Canadian government to blaze a primitive inland path, known then as the Lifesaving Trail and precursor of today's West Coast Trail.

The trail's usefulness as a rescue route declined as modern navigational techniques made the coast safe for ships. Today 's trail runs from Port Renfrew to Bamfield, with alternating -- and in some cases overlapping -- segments on the beach and inland. In places where the routes overlap, the choice between them can be tricky . H ikers who fail to consult the tide table might find themselves stranded and forced to backstack. There are no huts or shelters on the trail -- merely primitive campsites; two manned ligh thouses are available in emergencies.

We began hiking the trail on an inland segment, an evergreen milieu -- western red cedars, Douglas firs, mountain hemlocks and Sitka spruces. Trail crews have made every effort to make the trail passable; sawing through blown-down trees blocking the way, erecting wooden ladders and staircases to help hikers ascend sharp gradients, laying wooden boardwalks across bogs, imbedding stepping stumps in muddy gulches. At one point, we "log-walked" an eight of a mile from tree to tree, stepping in ridges hacked out of fallen logs.

Despite the crews' efforts, the trail is an obstacle course of rough spots -- half-hidden roots, slick stumps -- and we both suffered hard falls. With bridges across cxreeks and cable cars str ung over rivers, the entire trail is so complex that its components are numbered -- L26, say, for the 26th ladder from the Bamfield trail head -- like exits on the Interstate highway system. As with the highway system, th is numbering makes for ease in identifying trouble spots. A hiker might report, say, a broken rung on L33 to a warden.

Eventually the shade and dense cover of the trail's inland segments become monotonous, and it is a relief to come to a beach access point. Although footing is a problem in the loose sand or gravel, the beach is where the action is. The bird life -- crows, sandpipers, flocks of gulls, occasional great blue herons -- the sun and open horizon, the fresh air all restore sagging morale.

And here the power of the sea is inescapable. As the sea chews away at the sandstone cliffs, it carves rocks into contorted shapes and gouges t unnels through headlands. (At low tide some of these tunnels afford hikers passage to the next beach.) We passed blowholes that breakers had blasted into tidal shelves. As the breakers barrel through them, these holes throw up spray like geysers.

It is an easy trip from Seattle via ferry and logging roads to Port Renfrew, the southern terminus of the trail. We set up camp on an Indian reservation -- after paying Chief Art Jones $4 -- and began to prepare for the upcoming week of hiking. The next morning we checked in at the warden station and arranged for a boat ride across the bay to Thashers Cove. This short-cut is worth the $5 (Canadian) cost, because it bypasses five miles (and at least that many hours) of the most arduous, viewless trekking on the trail.

From the beach at Thrashers Cove, we headed several hundred fet up a series of steep ladders, up to a wooded crest and a long, sinuous route through the coastal rain forest. All afternoon we were immersed in woods bordered by skunk cabbage and salal, a wiry shrub festooned with purplish berries that were edible but not very tempting.

We had been warned, but the demands of the first day's hiking still came as a shock. The space between one foothold (which might be a root arching over the trail) and the next (w hich might be an imbedded rock) was almost always too wide -- we were constantly stretching. And beach hiking, though less claustrophobic, also had its hazards: sand that gripped the boots, surge channels that blocked the way. (The latter are breaks in the rock shelf, enlarged by the sea until they become reverse creeks: At high tide water rushes in and fills the channels. Some are so wide and deep that the hiker must consult a tide table ahead of time to make sure he will be able to cross them. Otherwise, he will have to take the inland route.)

Although every day turned out to be as taxking, in its own way, as the first, each also had its rewards, whether successfully negotiating a difficult section of the trail or watching a bald eagle soar 300 feet below us.

In particular there was a day of beach hiking in which we confronted surge channel after surge channel. The Sierra Club guidebook had warned about one channel, flanked by slippery shelves and overhung by a waterfall, that was supposedly passable only at a low tide not exceeding 5.4 feet. The table indicated we would arrive exactly at low tide that day, but the tide line wouldn't drop below 5.9 feet. We decided to take the gamble. If we were wrong, it would mean a mile of backtracking to the previous inland access.

We were right -- and wrong. The waterfall was all but defunct, but the shelves were slick with algae. As swells rolled in and sagged out, we surveyed a boulder-top route that would take us down into the channel and across the 12-foot gap. As a surge began to ebb, one of us stepped down.

And, three rocks later, slipped. It wasn't a hard fall, just an unnerving one that soaked boots and legs. The only course was to stay down in the channel, slog across the bottom, wriggle out of the pack, heave it up on the other side and haul yourself up over its sheer edge. The second of us did better -- only one foot drenched. Ten minutes later, when we'd wrung out our socks and collected ourselves, the tide had rolled so far in that the channel was truly impassable.

Three more times that day we negotiated similar channels, the last requiring a running start and a leap from one side to the other. These were heady successes, but there was also a disappointment. On the hike's last day, we opted for a beach route and found ourselves stalled on a headland, looking over a 15-foot drop to the next stretch of shore. The backtracking cost us an hour.

Interspersed with these adventures were extraordinary sightings: a bald eagle, cruising over treetops, fully 300 feet below our lighthouse vantage point; a pair of tail-heavy sea otters scurrying with tippy gaits across the beach; a vast congregation of glaucous-winged gu lls, pacing and preening on a rocky flat, breaking apart and reforming as we hiked through them; an Indian petroglyph, carved into a tidal shelf, depicting a sea devil with outsized horns.

Snails and seaweed encrusted some of the flat, hard tidal shelves, miles of which were exposed between headlands at low tide. Such shelves made for easy hiking, and it was tempting to cross them at full speed. But to do so would have meant missing out on a wealth of wetland life. Pools gouged into the shelves harbor a variety of small fish, mollusks and seaweeds. Against the orange sandstone, the deep blue-greens in the pools produce a striking contrast. Corals, sea urchins and mussels crowd with algae and flat, black, creping seaweed for space on the pool walls. Miniature skates and crabs scuttle along the bottoms.

As we walked along the shelves, occasionally a bobbing kelp head offshore would give the impression of a surfacing whale or sea lion. With Pacific gray whales surfacing a few hundred yards offshore all summer on their southward migration, sightings are very common -- practically everyone we met had seen them. Orcina (killer whales) are also frequently seen. And although the whales eluded us, we saw a colony of sea lions on a rock off Carmanah Point one day.

The people we met en route were not ordinary backpackers. One hardy fellow dealt with a surge channel by removing his pack, grasping it by the strap, winding up like a discus hurler, flinging it across the gap and leaping after it unencumbered.

By the wide, cold Klanawa River, we chatted with two young Californians who had spent several weeks working at a fish cannery and then hiked cross-country in Alaska's Denali National Park, breaking their own trail. The morning was cloudy and chilly, but when we accidentally dropped a walking stick out of our cable car into midriver, one of them astonished us by offering to dive in after it.

The Indians who ferried us across Nitinat Narrows, the outlet of a large tidal lake that bisects the trail, carried extra cargo; several tubfuls of salmon they had just pulled from the sea and a baby seal they had plucked from a rock. While the seal arched its head back and snapped upside down at anyone who came too close, the boat's pilot and his 10-year-old son joshed back and forth about whether they would make a meal or a pet out of it. (We suspect that the father prevailed.)

One bright morning we visited the lighthouse at Carmanah Point and were given a tour by t he attendant, Eric Van Rooyen. He and his wife alternate with another couple on 12-hour shifts so that the beacon and its diesel generator are never unwatched. But the Van Rooyens are well accustomed to the remote life -- they both come from lighthouse-keeping clans.

We had just a taste of that remote life along the West Coast Trail. In all, it was a magnificent, larger-than-life adventure -- and being physically taxed to the limit is an experience everyone ought to have at least once. The trail took its toll. But it also gave us the gift of its terible, feral beauty.