The Rio Brazos drops out of the high Tusas country through its spectacular box canyon above Tierra Amarilla — a freestone of real character, fed by big snowmelt off the Brazos cliffs and running cold and brawly in spring before settling to a friendlier size by summer. It holds wild browns and rainbows, and on the right flow it's a genuinely good river. The honest caveat is access: a great deal of the Brazos runs through private land, and the public reaches are limited and worth researching carefully before you travel — this is not a turn-up-anywhere river. Where you can fish it legally, it's classic Rocky Mountain freestone work: attractors and a dropper through the runs and pockets, heavier nymphs when the snowmelt is still pushing. Best after runoff clears in early summer and again in the autumn cool.

• Mixed

• Aquatic life: Supporting