Participants in the Scott Air Force Base Bataan Death March Memorial Ruck Challenge line up to weigh their backpacks on scales so they can be categorized into one of three weight groups. Marchers had staggered starts, based on the weight of their packs, with "heavy" category marchers getting a head start on the others. The march began after a brief 7 a.m. ceremony on the Parade Field Saturday morning at Scott AFB, and about 100 military personnel from Scott and other bases participated. The march honors the 76,00 American and Filipino World War II prisoners of war who were force-marched 80 miles in the heat and humidity of the Phillipines by their Japanese captors. Those soldiers were subjected to physical abuse and even murder, and thousands died, hence the name "Bataan Death March." The SAFB march involved walking or running a course around the perimeter of the base, a distance of about 6.5 miles, and participants had to walk the course twice - about 13 miles total - to complete the challenge. In addition to the sheer distance involved, they wore the weighted backpacks - or rucksacks - weighing either 15, 25, or 40 pounds -- or in a few instances, even more.