The Mountain Defense League Records represents the administrative records of the Mountain Defense League (MDL) for its three decades existence, and the work of both Bryon Lindsley and Pandora Rose as former presidents of the MDL. The majority of the collection consists of records from a variety of federal, state, and private organizations including legal documents, legislation, newsletters, annotated maps, and publications.  The MDL worked in conjunction with several federal agencies, most notably the Department of the Interior, U.S. Department of Agriculture, U.S. Forest Service, and the Bureau of Land Management. The collection is divided into two major series: Administrative Files and Environmental Research Files. The Administrative Files series is divided into five subseries: General Office Files, Correspondence, Legal Files, San Diego Environmental Review Board, and Sierra Club, San Diego Chapter.  The Environmental Research Files series is divided into five sub-series: Local Environmental Projects, General Plans, National Forests, Soil Surveys, and Publications.

Byron Lindsley Jr. founded the Mountain Defense League (MDL) in 1973 as a small, grassroots organization that worked in San Diego County to preserve and protect the natural environment from encroaching developers. In particular, disputes with developers at Middle Peak, Mt. Laguna, and Palomar Mountain were some of the MDL's most notable projects.

33.92 Linear Feet

The copyright interests in some of these materials have been transferred to or belong to San Diego State University. The nature of historical archival and manuscript collections means that copyright status may be difficult or even impossible to determine. Copyright resides with the creators of materials contained in the collection or their heirs. Requests for permission to publish must be submitted to the Head of Special Collections, San Diego State University, Library and Information Access. Permissions is given on behalf of Special Collections as the owner of the physical item and is not intended to include or imply permission of the copyright holder(s), which must also be obtained in order to publish.  Materials from our collections are made available for use in research, teaching, and private study. The user must assume full responsibility for any use of the materials, including but not limited to, infringement of copyright and publication rights of reproduced materials.

This collection is open for research.