The Crown Jewel in the Park's Crown. The M65 "Atomic Annie" is most certainly the most devastating cannon built and used after the second World war. With a 280mm bore and a 30km range the M65 could deliver the W9 Shell onto forces when at the time the job could mainly be done by large expensive (and at the time) inaccurate missiles, or large, slow bombers that had to make ot to their target before releasing their payload and vunerable to interceptors. The W9 was "Gun Type" Weapon the second only developed after the "Little Boy" type that was dropped on Hiroshima, and much like Little Boy The W9 had a 15 kiloton explosive yield. The M65's design was based off of the German Krupp 283mm K5 Railway Gun and carriage and began development in 1949. By 1953 one was able to be shown at the inauguration parade of US President Dwight D. Eisenhower and later that year was live fired at Frenchman Flat, Nevada Test Site s part of Upshot-Knothole under the codename of Grable. After the successful testing of the M65 (which would prove to be the weapons only live firing of a nuclear warhead) more guns were ordered, however the expensive nature of each weapon at $800,000 limited the production to 20 guns all made by Waitervlite Arsenal in Eastern New York. Although the M65 would soon quickly be replaced by growing advances in rocketry technology creating better ballistic missiles the M65s would stay in American service until 1963. The M65 shown in the picture is actually the very weapon that underwent live fire in Nevada and was restored by the U.S. Army Field Artillery Museum back in 2010 for display.