The California files (1941-2019) sub-series consists largely of research files, reprints, sketches, site survey reports, and correspondence pertaining to Fort Irwin, San Diego, Santa Barbara, San Bernardino, the Mojave Desert, and Joshua Tree National Park. The files also contain Warren’s research files on the San Dieguito and La Jolla complexes. Files from Warren’s work at California universities such as the University of California Santa Barbara (UCSB) and the University of California Los Angeles (UCLA) are included as well.

Organizational records (1960-2021) sub-series contains meeting notes, correspondence, conference programs, research files, and financial records from von Till Warren’s involvement in various organizations. The Nevada Humanities Committee, Friends of Nevada Wilderness, Clark County Comprehensive Planning, the National Trust for Historic Preservation (NTHP), Preservation Association of Clark County (PACC), and Soroptimist International are represented. There is also overlap with organizations such as the GCAC and GHS.