This record of siting a geologic repository for high-level radioactive wastes (HL W) and spent fuel describes the many investigations that culminated on Demnber 22, 1987 in the designation of Yucca Mountain (YM), as the site to tmdergo detailed geologic characterization. It recounts the important issues and events that have been instrmnenta1 in shaping the course of siting over the last three and one half decades. In this long task, which was initiated in 1954, more than 60 regions, areas, or sites involving nine different rock types have been investigated.