For some people, the word “kamchatka” triggers memories of 12-hour stints staring at the board game Risk and plotting how to conquer that isolated Siberian landmass in their quest for world domination. A select few might know it as Russia’s proving ground for missiles and long-range weaponry. Then there are the rest of us: The diehards who want to visit a wilderness where 20-plus-inch rainbows snarf mice from the river surface like they’re hapless mayflies. On Kamchatka, such tales are more than rumors: These trout have a short summer, and with limited time to pack on the pounds, they’ll hit anything. This place is everything a U.S. angler dreams about—but getting here is half the adventure.

Kamchatka juts 780 miles into the Pacific Ocean, a peninsula almost the size of New Zealand with less than a tenth of the population. A single road runs only partially along its length, most of it dirt. The landscape is stunning, studded with 160 volcanoes and 100,000 rivers and streams. Most of those waters hold native rainbow trout, and most of those trout have never encountered a human being.

We took off from Anchorage and landed in Kamchatka's only city of any size, Petropavlovsk-Kamchatsky, which is home to most of the nation's nuclear submarine fleet and completely isolated from the rest of the country. Navigating the vast wilderness beyond it requires a helicopter, but the available craft aren't exactly new. We endured a three-hour bus ride to a field where our whirlybird was packed with anglers, who then unloaded at various outposts during the next four hours of hopping and dropping. My buddies and I, along with our guides from the Best of Kamchatka, were the last stop. Our mission was to fish the spring-fed Dvukhyurtochnaya River (the Two-Yurt River to us) over the next six days, stopping at primitive camps every night of our 50-mile-long float.

Upon arriving, we found the river all but choked with fish. We’d heard this was one of the tougher seasons in years, with fewer salmon returning to the system and subsequently fewer big rainbows following them upstream. My first day was frustrating, with just a few swipes at my fly. Nothing came tight until late in the day, when I finally got my mouse-swinging technique down. Once my buddies and I started to understand the nuances, throwing rodents proved insanely addictive. We tried big dries, streamers, and even a few nymphs, but why bother when fish gobbled mice on the surface with reckless abandon, sometimes striking two, three, or four times before burying the hook?

And so it went for a week straight: Wake up, rig up, fish for trout and salmon all day—all while floating through some of the most remote and uninhabited scenery on Earth.

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