The Malleo River begins at Lake Tromen and winds its way south 35 miles, where it flows into the Aluminé. The water ranges from quick-moving to tranquil and easy to wade, and the catch from large trophies to smaller fish. Most of the river is mid-size freestone, save for an area in the meadows section of Olsen Ranch that's a small-gravel, spring-creek environment.
Huaca Marnuil Creek, a small tributary to the Malleo, is located entirely within Olsen Ranch.
- Season: Huaca Mamuil Creek, November through December; Malleo River, January through April
- Catch: Browns and rainbows, 2 to 5 lbs.
- Accommodations: San Huberto (Olsen Ranch)
