In 1789, Alexander Mackenzie traveled the 1,125 miles of the immense river in Canada that now bears his name, in search of the fabled Northwest Passage, only to confront impassable pack ice. In 2016 the acclaimed memoirist Brian Castner retraced Mackenzie's route by canoe in a grueling journey - and discovered the passage he could not find.

Disappointment River is a dual historical narrative and travel memoir that at once transports listeners back to the heroic age of North American exploration and places them in a still rugged but increasingly fragile Arctic wilderness in the process of profound alteration by the dual forces of energy extraction and climate change. Eleven years before Lewis and Clark, the Scottish explorer Alexander Mackenzie actually crossed the North American continent with a team of voyageurs and Indian guides. Before that he was the first to discover a route to the Arctic Ocean from the Great Lakes, along the river he named Disappointment because he believed he'd failed in his mission to find a trade route to the riches of the East. In fact he had - he was just two-plus centuries early.

In this book, Brian Castner not only retells the story of Mackenzie's epic voyages in vivid prose, he personally retraces his travels in an 1,125 mile canoe voyage down the river that bears his name, battling exhaustion, exposure, mosquitoes, white-water rapids, and the threat of bears. He transports listeners to a world rarely glimpsed in the media, of tar sands, thawing permafrost, remote Native American villages, and, at the end, a wide open Arctic Ocean that is quickly becoming a far-northern Mississippi of barges and pipelines and oil money.