The Lunar Roving Vechicle (LRV), also known as Moon Buggy, was used as a form of transportation on the surface of the Moon during the Apollo program.
What system did the astronauts use for navigation purposes whilst in the LRV?
I assume the astronauts lost sight of the Lunar Module (LM) and they had maps with them and could have used an inertial navigation system to produce selenographic coordinates telling them where they are on the surface of the Moon.