An examination of the possibilities for high-volume automotive transportation in the central city by deep underground tunnels and parking areas. The costs of conventional urban surface highways and of underground highways are presented. One interpretation of the data is that before the end of this century, if trends continue, it might be cheaper in many cities to move and park cars underground. Some design and operating features of underground construction and travel are considered. The study concludes with examples of what highway needs might be if all the users of mass transit systems were transferred to passenger cars in Los Angeles, Chicago, and Manhattan, and it offers some suggestions for future study and technical development of the underground-highway concept.
Hoffman, George A., Urban Underground Highways and Parking Facilities. Santa Monica, CA: RAND Corporation, 1963. https://www.rand.org/pubs/research_memoranda/RM3680.html. Also available in print form.
Hoffman, George A., Urban Underground Highways and Parking Facilities, RAND Corporation, RM-3680-RC, 1963. As of February 15, 2024: https://www.rand.org/pubs/research_memoranda/RM3680.html