WORLD CLASS SEA-RUN BROWN TROUT FISHING

Each season, up to 85,000 sea-run brown trout migrate through the legendary Rio Grande, making it one of the most productive and consistent fisheries for large anadromous browns anywhere in the world. During the peak months, anglers can expect to hook into powerful sea trout averaging 7 to 17 pounds—with chances at much larger fish.

While much has been written about the Argentinian stretches of the Rio Grande, far less is known about the upper reaches of the river, just across the border in Chile, where fertile, undisturbed farmland and vast estancias hold water that's seen very little angling pressure.

Here lies Estancia Las Segadas, a 400,000-acre working ranch that, along with neighbouring estancias, has been in the same family for two generations. Now the next generation has opened its doors to international anglers for the first time—offering access to pristine, exclusive stretches of the Rio Grande and its diverse network of lakes, spring creeks, tributaries, and beaver ponds.

The Rio Grande Lodge, situated deep within the estancia on the southern bank of the upper Rio Grande, places you in the heart of this wild fishery. To the west flows the Rio Blanco, draining the glacier-fed Lago Blanco, while spring creeks and smaller waterways wind inland across the private lands. This is Patagonia at its most rugged and rewarding.

The Rio Grande is an easily waded river, its gravel bottom shaped by centuries of glacial deposits from the Andes. In Chile, nearly the entire southern bank west of the border is privately accessed, and anglers with Isolation Outfitters enjoy privileged entry to waters that are otherwise unreachable.

Beyond the famed sea trout, this stretch of the Rio Grande also sees runs of King Salmon and Steelhead, and holds populations of resident brown and rainbow trout, along with the occasional Brook Char – making for an unexpectedly diverse angling experience.

After a complete refurbishment over the winter of 2025, the Rio Grande Lodge will welcome its first guests in February 2026. If chasing truly wild sea-run brown trout in un-pressured water is on your bucket list, this is a destination that should not be missed.

FISHING THE RIO GRANDE

The majority of the Rio Grande river system is sited in Chile, west of the border with Argentina. On its true right bank sits Rio Grande Lodge nestled between the Rio Grande and Lago Blanco to the south, with the Rio Blanco flowing nearby.

Prepare for ridiculously strong gusts and constant wind. Calmer days will then be a blessing! The undulating terrain further up the river does provide greater protection from the worst of the wind.

On a positive note, the prevailing winds blowing from the Andes towards the sea do actually assist casting across and downstream. Plus the resultant ripple on the surface, together with shallow water that is stirred up from the wind, helps to hide you and your tippet and flies from these wary fish.

These southern hemisphere sea trout should be fished for with a careful presentation, despite the heavier gear adopted on this mid-sized river. They are easily put down with a careless cast or a fly landed heavily and you can spook the lie with careless and unnecessary casting. Generally, the further up the Rio Grande you fish, the clearer the water can be, so expect less turgid water on the Chilean side than towards the river mouth.

For smaller waters such as the virgin tributaries further up the estancia and the tiny spring creeks, don’t forget to pack a single handed rod of 5 or 6 weight, and matching lines, leaders, lighter tippet and suitable flies.

The estancia comprises pampas grasslands rising into undeveloped foothills, with clear lake-fed streams carving out their winding pathway to the Rio Grande.

Local birdlife includes soaring Andean condors with a wingspan almost as long as your fly rod, gaggles of Greater Magellan geese and some Chimango Caracara (a falcon subspecies).

Expect to see the ubiquitous guanacos and elusive South American grey foxes; perhaps even a rare Fuegian fox (Patagonian red fox) – the second largest native Canid in South America.