scree

Above 13,000 feet, the trail disappears, turning the final push into a steep, tortuous slog up loose scree guided only by cairns — stone towers left by previous climbers to mark the way.

Up in the mountains, they cling to “pockets in shifting scree, where gravel and rocks form barely the idea of soil,” Chips said.

They parked on the far edge of the outcrop, then continued on foot through a sloping scree field of glassy black stone until they reached a view of the mud flats to the east.

The first four days featured very limited access points and the entire route required the “North Cascades’ finest bushwhacking,” glacier travel, snowfields, scree, boulder and talus fields, and scrambling.

To the southeast he noted an alley filled with scree — it was a timeworn ball court, 350 feet long and 16 feet wide with sloping sides.