The reliance on static underground features is LGPR’s advantage as a complement to other localization methods, even in fair weather conditions. The use of a subsurface map reduces the need for continual modifications to high-resolution road maps. Fusing GPS, lidar, camera, and LGPR results yields a system that can accurately localize even when one of the sensing modes fails. This “fail-safe” capability will be necessary to the development of dependable autonomous vehicles that can handle demanding ground environments.