It was just about ten minutes after noon on Thursday, August 20 when the Glacier Explorer rounded Aligo Point at the tip of Harris Peninsula and entered Granite Passage, which would lead us into Harris Bay and its farthest extent, Northwestern Fjord. The morning had taken us from Seward down the length of Resurrection Bay and then along the fjords and peninsulas of Kenai Fjords National Park.

Appropriately enough, our course was northwesterly. As we sailed up Granite Passage, Harris Peninsula was to starboard and soaring, slender Granite Island was to port.

As we sailed along, the crew served our lunch of wraps and chips while we took in the scenery.

Beyond Granite Island, we entered Harris Bay. Behind us, the Gulf of Alaska stretched south to the Pacific, and then, tantalizingly, a straight line would not touch land again until Antarctica.

As we continued toward Northwestern Fjord proper, the plant communities along the shore began to change. Near the mouth of Harris Bay and on Granite Island, spruce and hemlock forests are well established, but as we traveled toward landscapes that had more recently been glaciated, the forests became shrubbier and brushier. But although there was a general trend, in some spots, as in the image above, it was obvious where ice had rested relatively recently on the slopes. Throughout the bay and the fjord, microclimates affected by the proximity of the icefield, the amount of sun a slope receives, and exposure to winds and storms, created areas of greater or lesser vegetation. Because of the cooling effect of the visible ice, but more importantly the immense Harding Icefield, the tree line altitude remained suppressed.

But still, regardless of the micro-climate variations, the general trend of the phenomenon known as forest succession is that the glaciers leave behind bare rock, which lichens then begin to break down. The thin, loose soils created by the lichens are enough for hardy pioneers like fireweed to germinate in. These are followed by shrubby willows and stands of alder, which fix nutrients into the soil. Eventually, spruce and hemlock replace the alder and willow as the forest reaches maturity.

Before long, we crossed a shoal that indicated the extent of Northwestern Glacier in 1900. Captain Mark pointed out the shallows along either shoreline that betrayed the glacier’s terminal moraine from that time. This shoal also marked the divide between Harris Bay and Northwestern Fjord.

Some of the slopes, such as those pictured above, clearly showed glaciers that had shrunk considerably compared with the width of the valleys they had once carved.

Even after Northwestern Glacier, which had once filled the fjord, retreated well beyond the 1900 terminus, Northwestern Fjord had been largely unnavigable for decades because of the hazards posed by the icebergs clogging the fjord and the bay. Captain Mark said that taking into account how recently the fjord opened, and then multiplying the number of tours, charters, research trips, and private boats that had ventured out here, we were in a place that had only ever been visited by fewer than 300,000 people.

We passed Striation Island, deeply grooved and scoured by the retreating Northwestern Glacier, rounded a final bit of coast, and then got our first glimpse of Northwestern Glacier, hanging onto a cliff face beneath the Harding Icefield.

But before we reached Northwestern Glacier, there were a few other things to notice, including the view back down the fjord (above) and a broad, glacier-carved valley with a glacial stream reaching the fjord to starboard.

But then we were upon Northwestern Glacier, which greeted us with an icefall as upper portions of the glacier broke loose and tumbled past exposed cliff face.

On this August afternoon, Northwestern Glacier dipped its snout into the waters of the fjord only in a few isolated places. Captain Mark informed us that although the glacier has retreated catastrophically over the past century, it is relatively stable at the moment, surging forward somewhat over the winter and then retreating over the course of the summer. He said that one of the things he liked about visiting Northwestern was that he never knew exactly what to expect from season to season.

The distinctive blue ice of a glacier is caused by the density of the ice. Glaciers are formed when snow fails to melt from season to season, piling up and crushing itself under its own weight. The six-sided lace of each individual snowflake is crushed as the air is pushed out, creating an ice that is far denser than ice cubes, the frozen surface of a lake, or a frozen sidewalk.

The ledge that Northwestern Glacier tumbles over is some 2,000 feet above the surface of the fjord. Although it appears static and impregnable in photos, all that mass of ice is dynamic. The sound of rushing water was ever present as the glacier melted in spectacular icefalls, surging cascades, or violent gushes from below.

Video: Sean Santos and Brandon Hayes

On the icebergs that littered the fjord, an entire colony of Harbor Seals rested. More in the water were waiting for additional icebergs to haul out onto.

The crew fished an iceberg from the fjord so that we could touch it and view it up close.

We stayed at Northwestern Glacier for about half an hour as Captain Mark slowly circled, careful not to get too close. For a long while he was silent, allowing us to take in the place’s majesty and wildness before continuing his narration.

Soon it was time to leave, and at about 1:45, Captain Mark turned the Glacier Explorer down Northwestern Fjord. But although we had begun the return trip, there was still plenty to see and many hours to go before we reached Seward.

Not far to the south, as the fjord widened, Ogive Glacier clung to its western slopes.

Ogive just barely touched the fjord, its terminus carved into ice caves with walls striped by sediment layers embedded in the glacier.

Wholly different from the drama of Northwestern Glacier, Ogive Glacier’s striped pinnacles of ice and sediment boasted their own beauty and elegance.

Immediately south of Ogive Glacier, Anchor Glacier clung to a steep slope not unlike Northwestern Glacier. Captain Mark pointed out that Northwestern would eventually share Anchor’s fate and retreat, likely irrevocably, up toward the icefield.

Both Ogive and Anchor Glaciers spill down from a point on the icefield that, at 6,450 feet, is the highest in Kenai Fjords National Park.

After passing close by Ogive and Anchor, Captain Mark maneuvered the Glacier Explorer farther from the shoreline. Out toward the middle of the fjord, back within sight of Northwestern, he pointed out that from this spot, we could see five major glaciers: Northwestern, Ogive, Anchor, Southwestern, and Northeastern.

He told a brief anecdote about a glaciologist from Hawaii who had hired him to go out to specific locations so that the researcher could take updated images of glaciers he had photographed years earlier for comparison. One of the spots they had visited was where we now were. Because the day was so beautiful, Captain Mark decided to give us a 360-degree view and slowly circled the boat so we could take in the fjord, the mountains, and the five glaciers. Then he decided we should go around a second time.

All too soon it was time to leave in earnest, and we rounded a beautiful, red-orange hued island as we started back. Its name is Erratic Island because it is actually a giant boulder left behind by the retreating glacier.

Back in Harris Bay, we spotted a Humpback Whale.

While we were watching for another Humpback Whale who had shown himself briefly, we spotted a pair of Sea Otters.

Although obviously aware of the boat’s presence, they moved relatively close as they made their ways east toward Granite Passage.

Then they stopped to regard us before one, then the other dove beneath the surface and vanished.

After being hunted to near extinction for their fur, Sea Otters have rebounded quite a bit in the past century. Naturally curious and gregarious, they are generally beloved and are protected by their status as an endangered species. This was not always the case. In addition to their being hunted for pelts in the nineteenth century, American soldiers stationed in Alaska during World War II sometimes shot them for sport from the decks of ships.

The coast of Kenai Fjords National Park continued for many miles to the southwest, but our time to explore was growing short.

The usual route for tour boats departing Northwestern Fjord and Harris Bay is to go back through Granite Passage, shielding the boats from the brunt of wind and waves from the Gulf of Alaska. But since it was so exceptionally gorgeous and calm, Captain Mark took us along the western, gulf-exposed side of Granite Island.

Then, for a special treat, he maneuvered us into Taz Basin and a secluded little cove on the seaward side of Granite Island to see what we might find.

And what did we find? A mother Sea Otter with her baby resting on her belly while she floated on her back.

She only tolerated our presence in the cove for a few moments before taking her youngster and diving beneath the surface.

As we approached the island’s southeastern tip, called Granite Cape, the trees and most other vegetation rose away from the sea leaving expanses of exposed rock that were not present in the cove or on the leeward side of the island. Captain Mark explained that the extent of exposed rock indicated where waves pounded the island during intense winter storms.

The thought, particularly on such a beautiful day, was astonishing.

As we rounded the cape, the Chiswell Islands and Aialik Peninsula came into view. The islands were our next destination.

But first, one more Humpback Whale would come near the boat as we passed the mouth of Granite Passage and said goodbye to Northwestern Fjord.