“A mellow intro followed by a very steep ascent.”
— Andy Dandrews
The entire drainage below Arapaho Glacier is closed to travelers of any sort/campers, since it is owned by the City of Boulder and supplies the city's drinking water. Though some of the snow/ice routes up the glacier look tempting, they are illegal, and these closures are strictly enforced.
Start at the Fourth of July Trailhead just past the Eldora Ski Area, and take the trail to the Arapaho Pass Trail. The trail ascent is extremely steep and requires caution.