Robert C. (Bob) Speed was a major contributor to the understanding of Nevada geology. Bob Speed’s work was based on thorough, detailed geologic mapping, and many of his geologic maps were published through the Nevada Bureau of Mines and Geology and the U.S. Geological Survey. He and Ron Willden are the authors of NBMG Bulletin 83, Geology and Mineral Deposits of Churchill County, Nevada and its accompanying geologic map. Bob’s maps published through the USGS include the Sodaville quadrangle (MF-1300), the Mina NW quadrangle (MF-1487), Huntoon Valley quadrangle (Open-File Report 81-0274), and Little Huntoon Valley quadrangle (Open-File Report 84-0503). However, as with all geologists, Bob Speed did not have time to publish everything he did, including much of his geologic mapping. NBMG was able to scan paper copies of many of his unpublished and preliminary geologic maps. Major groups of maps are in the following areas: the Candelaria Hills–Mina, West Humboldt and Stillwater Ranges–Greater Lovelock, Toiyabe and Toquima Ranges, and Clan Alpine and Augusta Mountains. These are now provided as PDF files that can be downloaded for free from the Bureau’s website. We welcome contributions of any additional unpublished work by Bob Speed to add to this collection.