Jason Allen Graves, 24, died Aug. 27. Graves fell during the descent from the summit of the 13,810-foot-tall Gannett Peak in Fremont County, Wyoming, according to a GoFundMe created by his loved ones.

As the couple reached the summit of Gannett Peak (13,804 ft), they inscribed HP12 next to their names in the summit’s register, marking that spot as their twelfth visited highest point. It was a goal ...