North America was not the land of milk and honey that early explorers sought. It was a rocky, cold, foreboding obstacle blocking the way to the riches of Asia. The Vikings, Hernán Cortés, Juan de Fuca, Martin Frobisher, Sir Francis Drake, and virtually every captain dispatched across the pond by a European king between 1500 and 1800 hunted for the Northwest Passage to Cathay. The English got close in Hudson Bay, before its namesake was left to die in a dinghy by his mutinous crew. Frenchman Samuel de Champlain and his truchement made a valiant effort, plunging into America’s interior with paddles, snowshoes, and bibles, tasting all five Great Lakes along the way for signs of salt.

“For every businessman who sought to strip the New World of resources, another just wanted to get on to the real market in China,” writes Brian Castner in his new book, Disappointment River: Finding and Losing the Northwest Passage (Doubleday, $29). Such was the case with Alexander MacKenzie, the central character in Castner’s book. MacKenzie was just 25 years old in 1789 when he set out across Canada’s icebound Northwest Territories to find a route to the Pacific. Canada was not the pastoral, Tim Hortons–laced wilderness-nation then that it is today. The northwest corner of the continent represented one of the last unexplored and unmapped regions on the planet—along with interior Africa, Australia, and both poles. Russian America stretched from Kodiak Island, off the coast of Alaska, to Fort Ross, near San Francisco. The Spanish owned a third of what would one day become the continental United States. Napoleon was planning an invasion of the American West, and it was a toss-up whether the British or Americans would ultimately control the 250,000-square-mile plot of land between the Rocky Mountains and the Pacific Ocean.

Castner does a masterful job in the first half of the book chronicling MacKenzie’s adventures in barbarous 18th-century North America: his arrival on an East River pier in Manhattan; navigating New York City’s press gangs, breastworks, and patriot and Tory allegiances in the opening days of the Revolutionary War; escaping over the “endless mountains of the Appalachians” to Montreal; and securing a post as a clerk counting pelts in the booming fur trade.

The voyageurs, manageurs du lard, and bourgeois that MacKenzie worked with had already discovered and mapped much of the continent by then. (French Canadian canoe men paddled 55 strokes per minute for 18 hours a day and hauled an average of 180 pounds of cargo over miles of portages on thousand-mile journeys.) The last blank spot on the map lay deep in the pays d’en haut—the “upper country,” where MacKenzie’s bosses tasked him with finding a river by which they could ship thick, northern furs directly to Chinese tailors in Kiahtka and Canton.

MacKenzie undertook two expeditions. The first ended in failure. The second landed him near the shores of Vancouver Island, where he became the first white man to cross North America. Castner follows the first journey, both on foot and on paper, using MacKenzie’s journals, a few modern guidebooks, and seasoned locals to find the way. MacKenzie’s mission was plagued by ice, snow, lack of food, incompetent guides, horrendous weather, and the kind of malaise one associates with northland expeditions (read: Father Hennepin, Jean Nicolet, Lewis and Clark, Roald Amundsen). Castner and three alternating paddling partners do an excellent job tracking the route, and also achieving high malaise, on their 1,124-mile reenactment.

They begin in an 18-foot canoe on the Hay River, 850 miles due north of Missoula, Montana, and paddle the length of the MacKenzie River. (Locals call it the Deh Cho.) On the way, Castner and Co. are tormented by gumball-sized flesh-eating flies, deadly lightning storms, oceanic waves, ceaseless rain, prowling bears, thieving locals, Hyundai-sized rapids, and countless near-disasters. Castner’s gloves rot through. The food spoils. His gear gets soaked at least once a day. The weather gods seem dead set on drowning him. At several points, our hero sits with his head between his knees, wishing he could go home. “Brought low by a powerful god, and paired up in a boat with a Jew,” he writes, “it is no surprise that Jeremy and I started counting the plagues of the Deh Cho.”

Chapters in the second half of the book alternate between Castner’s journey and that of his forerunner. The mirroring shines at times: “For the first and only time, MacKenzie and I were sleeping on exactly the same rock on exactly the same day, united by both calendar and geography, precisely 227 years apart.” Other times, the reader is left without the landmarks or narrative mile markers needed to connect the two journeys, diminishing the innuendo that walking-in-the-footsteps adventures often pack.

Like the Fountain of Youth and the golden cities of El Dorado and Norumbega, seeking the Northwest Passage has been an obsessive pursuit for explorers.

Another miss is the book’s hook—ostensibly one reason Castner followed MacKenzie’s first expedition and not his second. Contrary to most history books, MacKenzie did find the Northwest Passage on his first go, but a global cooling event known as the Little Ice Age had frozen it solid. Finding a sea of ice at the mouth of the Deh Cho, the young explorer declared the route impassable and the mission a failure. Castner waits until the final pages to explain that global warming, in part caused by massive carbon extraction on the continent MacKenzie crossed, has since melted that ice and opened the Northwest Passage for seasonal business. Castner more than makes up for those shortfalls with excellent research and descriptions and surprising endurance as an explorer himself. Disappointment River not only carries the reader along; it also gives us a 21st-century view into the harrowing nature of exploration on the continent we now crisscross in climate-controlled sport wagons.

Like the Fountain of Youth and the golden cities of El Dorado and Norumbega, seeking the Northwest Passage has been an obsessive pursuit for explorers—and authors—since the New World was discovered. The English were particularly susceptible, believing that a direct path to China would loosen Spain’s grip on the Asian spice trade. Obsession begets obfuscation, and there were miscalculations along the way. One theory that lured many explorers to their demise was that seawater could not freeze, so if a captain could push through the pack ice surrounding the North Pole, an open and passable Arctic Sea awaited. Another suggested that Asia practically touched the northern shores of North America, leading English explorer Martin Frobisher in 1576 to kidnap and display an Inuit kayaker back in London as a “strange man of Cathay.”

In his book Ice Ghosts: The Epic Hunt for the Lost Franklin Expedition (W.W. Norton, 2017), Paul Watson cites a statistic that for three centuries after Columbus’s discovery, at least one captain, “drawn forth by the fierce need to discover that which defines our species,” searched for the Northwest Passage every 15 years. Watson’s subjects are Sir John Franklin, who sailed with two ships in 1845 to solve the riddle of the passage, and dozens of ensuing missions dispatched to solve the riddle of what happened to Franklin. As with most Arctic disasters, ice got them in the end, and all 129 officers and crew died.

Watson rode on the Canadian Coast Guard icebreaker that discovered the first of Franklin’s ships, Erebus, in 2014. (The second, Terror, would be found two years later.) The Pulitzer Prize–winning author recounts the original mission with gripping detail in the opening chapters of the book, then delves into the marine science and Inuit oral history that ultimately led searchers to the historic find. Watson weaves together past and present throughout the search and dives deep into the issue of climate change and the impact of melting sea ice on international trade, the Arctic environment, and politics—including the importance of the ship’s discovery to the Canadian government, which financed the 2014 expedition and now uses the find as evidence of the country’s sovereignty over what has become the fastest sea route from the Atlantic to Asia.

Most accounts of explorers freezing to death while trying to connect the Pacific and Atlantic oceans start in the East. Stephen R. Bown takes the opposite tack in Island of the Blue Foxes: Disaster and Triumph on the World’s Greatest Scientific Expedition (Da Capo Press, 2017). Bown opens the book in St. Petersburg and follows the secretive and massive 1733 Great Northern Expedition from Russia to the west coast of North America and the Northeast Passage. Czar Peter the Great, who built Russia’s first navy and was fascinated with the North Pacific, hired Danish explorer Vitus Bering to expand Russian influence across the sea to North America’s west coast. (Hence Russian America.) The mission included more than 3,000 scientists, sailors, soldiers, and artists, whose fate was kept under wraps for decades after the mission ended.

Documents from the journey are still hard to come by, and until now most accounts existed only in academic circles. Drawing on old and recently discovered sources, Bown follows the mission across a roadless Siberia to the Kamchatka Peninsula, where Bering and his crew constructed two boats. The true malaise begins shortly thereafter, on the North Pacific, where the ships lose touch and never reconnect. Mined largely from the journals of the second in command, Lieutenant Sven Waxell, and the expedition’s naturalist, George Wilhelm Steller, the epic tale of their eventual arrival in Alaska is a testament to the will, strength, savvy, blind faith, and luck required by boreal explorers of centuries past.

Porter Fox is the author of Northland: A 4,000-Mile Journey Along America’s Forgotten Border.