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Montana has been a destination for its world-class trout fisheries since the 1930s. Fly fishing for several species of native and introduced trout in rivers and lakes is popular for both residents and tourists throughout the state. Montana is the home of the Federation of Fly Fishers and hosts many of the organizations annual conclaves. The state has robust recreational lake trout and kokanee salmon fisheries in the west, walleye can be found in many parts of the state, while northern pike, smallmouth and largemouth bass fisheries as well as catfish and paddlefish can be found in the waters of eastern Montana. Robert Redford's 1992 film of Norman Mclean's novel, A River Runs Through It, was filmed in Montana and brought national attention to fly fishing and the state.

Since when has Montana been a destination for trout fisheries?
1930s