The, commonly called the is part of the Hiroshima Peace Memorial Park in Hiroshima, Japan and was designated a UNESCO World Heritage Site in 1996. The ruin serves as a memorial to the people who were killed in the atomic bombing of Hiroshima on 6 August 1945. Over 70,000 people were killed instantly, and another 70,000 suffered fatal injuries from the radiation.HistoryThe Product Exhibition Hall building was originally designed by the Czech architect Jan Letzel. The design included a distinctive dome at the highest part of the building. It was completed in April 1915 and was named the Hiroshima Prefectural Commercial Exhibition (HMI). It was formally opened to the public in August that year. In 1921, the name was changed to the Hiroshima Prefectural Products Exhibition Hall, and again, in 1933, to the Hiroshima Prefectural Industrial Promotion Hall. The building was located in the large business district next to the Aioi Bridge and was primarily used for arts and educational exhibitions.Atomic bombingAt 8:15 a.m. on 6 August 1945, Little Boy — the first atomic bomb to be used in war — was dropped by the United States Army Air Forces from the Enola Gay, a B-29 bomber. The force of the atomic bomb effectively obliterated the city of Hiroshima, Japan.