The "Baker" explosion, part of Operation Crossroads, a nuclear weapon test by the United States military at Bikini Atoll… https://www.rawpixel.com/image/8717924/photo-image-cloud-vintage-public-domainFree Image from public domain licenseSinking of the Japanese destroyer Yamakaze on 25 June 1942 approximately 110 km southeast of Yokosuku, Japan, photographed… https://www.rawpixel.com/image/8718080/photo-image-vintage-public-domain-worldFree Image from public domain licenseU.S. Soldiers walk toward the rising sun during the 10-kilometer road march at the 2013 Army Reserve Best Warrior… https://www.rawpixel.com/image/3315439/free-photo-image-soldier-trauma-2-mile-runFree Image from public domain licenseU.S. Army Sgt. 1st Class Desmond Burgess, an Army Reserve information technology professional assigned to the 200th Military… https://www.rawpixel.com/image/3319154/free-photo-image-pushup-exercise-running-copFree Image from public domain licenseMowing next 2 miles, traffic construction sign. Free public domain CC0 photo. https://www.rawpixel.com/image/6198338/photo-image-public-domain-nature-redFree Image from public domain licenseU.S. Soldiers compete in the ruck march event at the 2018 U.S. Army Reserve Best Warrior Competition at Fort Bragg, North… https://www.rawpixel.com/image/8727801/photo-image-light-public-domain-personFree Image from public domain license