Half Distance Boulder Triathlon Event Summary: Swim (1.2 miles): Athletes start at the east boat ramp of Boulder Reservoir, swimming counterclockwise in 62°F (17°C) water, exiting at the west boat ramp. Bike (56 miles): The 2-loop course begins at Boulder Reservoir, featuring freshly paved roads. It heads onto Diagonal Hwy, then Foothills Hwy, with short rollers and a fast downhill on rural Hygiene Rd. Athletes complete two loops, enjoying scenic views. Run (13.1 miles): Starting from ...