“Large” is a relative term, but boulders consisting of over 10,000 cubic feet of rock (a boulder 50 ft x 30 ft x 10 ft = 15,000 cubic feet, for example) can be found in association with a wide range of rock types, river systems, and their associated landscapes. Even so, the matching size and shape of the boulder and potential scar, along with the appearance of the slope beneath the scar, make good evidence for a positive identification of the boulder’s source. Assuming the scar is indeed the boulder source, the boulder traveled ~960 ft (just under 300 m) over the ground surface, descending ~350 ft ( about 110 m).