Motorcyclists competing in the Pacific Trails Endurance Run across California.
Thought to be Selected Originals from late 1940s material.
California, United States of America (USA).
Close up shot of a motorcycle starting and taking off - lots of dust and smoke. Various shots of the motorcyclists competing in the Pacific Trails Endurance Run across California. They are seen riding on the curvy roads, rough terrain, mud, water, on the mountain road etc. Several shots of the motorcyclists riding at night with their lights on - those seem to be the only lights around.
Possibly connected with 48/21 - MD.