Train for Success at the Oregon Half Distance Triathlon – With a Plan Built for Athletes 60+ You'll begin with a 1.2-mile swim in the gently flowing Willamette River, starting at Minto Brown Island Park. Thanks to the downstream current, you'll experience a faster, smoother swim, finishing at Riverfront Park in water temperatures averaging 65°F (18°C). The 56-mile bike leg unfolds over lightly rolling hills and flat, rural roads—ideal for steady pacing and speed. The 13.1-mile run loops ...