San Rafael - 02. Bridge at San Rafael Campground to I-70 (Black Boxes 1 & 2) (UT)
Alternate access point on river left that puts you in at the start of the First Black Box. It requires a hike of about a mile across the desert and down Lockhart Wash but cuts off the flatwater at the start. It may be a little long for hard shell kayakers but this is an option for packrafters to consider.