At 11:02 on August 9, 1945, an atomic bomb was dropped over Nagasaki, destroying almost the entire city and killing a vast number of people.
Wall Clock
This clock was recovered from a house near Sannō Shrine, approximately 800 meters from the hypocenter. Damaged by the blast, it stopped permanently at 11:02, preserving the exact moment of the atomic explosion.
Nagasaki Before the Bombing
Nagasaki’s modern history began in 1571 with the arrival of a Portuguese ship. During Japan’s period of national isolation in the Edo era (1603–1868), it served as the country’s only official window to the outside world, permitted to trade with the Dutch and Chinese. After Japan reopened in the mid-19th century, Nagasaki flourished as a center of international trade, and many Western-style buildings were constructed. The city later developed into a major hub for shipbuilding. Following the wars with China and Russia, Japan entered World War II. Then, on a hot summer day in 1945, the atomic bomb was dropped, irrevocably altering the city and its people
Nagasaki on that day
The estimated number of casualties by the end of 1945 is as follows:
Deaths: 73,884
Injured: 74,909
The Water Tank of the Former Keiho Junior High School
This tank, located 800 meters from the hypocenter, was damaged by the blast wave and remains preserved today as a witness to the destruction.
The Disfigured Fire Watch Tower
Located 300 meters from ground zero, this tower was broken at the base by the blast.
Devastated Urakami Cathedral
The Urakami area holds profound historical significance as one of the earliest centers of Christianity in Japan, dating back to the late 16th century. Following the ban on Christianity in 1587, local believers endured centuries of secrecy and persecution until the ban was lifted in 1873. After centuries of secrecy, the faithful began construction of Urakami Cathedral, which was completed in 1925. It was the largest church in East Asia at the time, featuring imposing twin towers reaching 26 meters in height. The atomic bomb tore off the bell dome and reduced the entire structure to rubble, leaving only fragments of the walls standing.
The replica of the remains of a side wall of Urakami Cathedral
The statues were blackened by the blast, heat rays, and the fires that followed. The stone pillars were slightly shifted from their original positions.
The process of dropping the second atomic bomb on Nagasaki
On August 9, three days after the atomic bombing of Hiroshima, a second atomic bomb was prepared for deployment. The primary target was the arsenal and city of Kokura. However, visual confirmation of the target was required, and poor visibility over Kokura led to a change of target to Nagasaki. Based on coordinates, the intended drop point was the area near Tokiwa Bridge and Nigiwai Bridge, but it was obscured by cloud cover. When the bomber reached the Mitsubishi factory in the Urakami district, a break in the clouds allowed for visual identification, and the bomb was released. It detonated approximately 500 meters above the ground.
The projection mapping depicts Nagasaki before the bombing, the moment of the explosion, and the rapid expansion of the fireball, followed by the effects of thermal radiation, blast wind, fires, and radiation. The fireball is estimated to have reached a diameter of about 1 kilometer within seconds.
Nagasaki Atomic Bomb Fat Man
It was nicknamed “Fat Man” because of its round shape. The bomb worked by using conventional explosives arranged around a plutonium core to compress it, triggering a nuclear fission reaction.
Shadow Left by the Heat Rays
The shadows were formed because objects blocked the intense thermal radiation. Surfaces directly exposed to the heat were burned and discolored, while shielded areas remained unchanged. This contrast created the appearance of shadows. The atomic explosion at 11:02 produced many such permanent silhouettes.
Shadows of a ladder and a watch soldier
When he was just going down on the ladder.
Roof Tiles Exposed to the Radiation:
The surface of the tiles was scorched by the intense heat, causing bubbles to form. The closer the tiles were to the hypocenter, the larger the bubbles became. These vitrified tiles remain as silent witnesses to the extreme thermal radiation.
Physical damages caused by the heat rays
The intense thermal radiation ignited all flammable materials near the hypocenter. The extreme heat is evidenced by melted glass, roof tiles boiled into bubbles, and rocks scorched black. While the effect diminished with distance, within a 2-kilometer radius, the heat remained strong enough to char clothing, utility poles, trees, and other objects.
Bamboos with the Mark of the Heat Rays:
3 km away from ground zero.
The View of Yamasato Town from the Hill Opposite Ground Zero:
Scorched cobblestones from the shrine.
Melted coins
The damage was compounded by the fires that erupted after the initial heat wave and blast, making the overall devastation far more severe.
Even houses that were only partially damaged by the initial blast were completely consumed by the subsequent fires. In total, 12,900 houses were completely destroyed, and 5,519 were partially destroyed. The fires also significantly increased the number of casualties, as many individuals trapped under debris might otherwise have been rescued had the flames not spread.
Six Melted Bottles
400 m away from ground zero.
Soap
Shrunk by the heat. 400 m away from ground zero. The storehouse of Mitsubishi Shipbuilding Company.
The area around the GZ
The bones of a hand stuck with glass by the heat
The Lunch Box of a Girl Student:
This kori (woven bamboo food container) was found approximately 700 meters from the hypocenter. It belonged to a woman named Satoko Tsutsumi, whose name was written on the back. The rice inside was completely charred by the intense thermal radiation, preserved as a silent testament to the devastation.
Human damages by the heat rays
A few seconds after the light flash, intense thermal radiation struck human skin, causing unimaginable injuries distinct from ordinary burns. The severity depended on the distance from the hypocenter. In the most severe cases, skin was burned, eroded, and peeled away, sometimes exposing underlying tissue and bone. Within a radius of approximately 1.2 kilometers, the heat rays were often fatal. Close to the hypocenter, victims were instantly charred, and the extreme heat even caused the evaporation of bodily fluids.
The helmet with a skull sticked
These items of work clothing and a wartime cap were found 1.2 kilometers from the hypocenter, damaged by the intense thermal radiation.
The scorched right side of a face
The victim exposed to the heat rays
Scars caused by the heat rays
A boy with all of this back burnt by the heat rays
Models of Keloids
Damaged caused by the Blast
Within 1.5 kilometers of the hypocenter, all houses were utterly destroyed. Everything was gone, leaving only the fractured skeletons of reinforced-concrete buildings standing. The cracks and twists in these structures still trace the direction of the blast wave. People were hurled through the air by the force of the explosion or struck by countless fragments of glass and wood that flew like shrapnel.
Stairway from Zenza National Elementary School:
1.5 km away from ground zero.
Oak Tree
This oak tree, cut down 33 years after the bombing at a construction site, was found to contain countless embedded pieces of glass. Two cross-sectional slices from the trunk near the base have been preserved and are now used as display stands.
One-Pillar Torii Gate
Mitsubishi Weapon Factory at Oohashi
1.3 km away.
Iron Angles from a Factory
1.3 km away.
Shifted Railroad Bridge
Urakami Prison
Damaged Chuzei Junior High School
Fallen Roadside Trees
Human Damage caused by Radiation
The ionizing radiation released by the atomic bomb penetrated the human body, damaging cells and DNA. The severity of the injuries was directly related to the distance from the hypocenter. Within one kilometer, the radiation dose was so high that it was fatal to most people, often without causing immediate visible external wounds, demonstrating its insidious and deadly nature.
The harm extended far beyond instant death. Radiation injury affects the body at a fundamental level, leading to a range of delayed illnesses that appeared days, weeks, or even years later. These included various cancers, cataracts, and other chronic conditions. The suffering caused by the bombing, through these lasting health effects, continues to affect survivors and their descendants.
Discolored glass
A girl with diseases under the skin.
Rescue and Relief Activities
Rescue and Relief Activities
The bombing destroyed the pre-existing rescue and relief organization.
Surviving doctors and nurses began rescue efforts immediately but were severely hampered by a critical shortage of medical supplies and equipment. Amid the chaos, rescue trains bravely entered the still-burning areas near the hypocenter, transporting the injured to hospitals along the railway lines. The first organized external aid arrived in the evening with a team from the Navy Hospital, followed by relief units organized from local civil defense groups, who entered the city after nightfall.
Shinkozen National School Temporarily Changed into a Special Hospital
Relief team carrying a seriously injured person on a stretcher.
Child crying during treatment for burns.
Mother and child waiting for their turn to be treated.
Dr. Takashi Nagai
Dr. Takashi Nagai, an assistant professor at Nagasaki Medical College, was exposed to radiation during the atomic bombing. Despite suffering serious injuries himself, he immediately began rescuing survivors and devoted himself to studying the effects of radiation on the human body. As a doctor, his work later expanded into a broader vision for the restoration of his city and its culture, and a lifelong pursuit of world peace. Although he later developed leukemia and was confined to his bed, he continued his mission through writing until his death six years after the bombing. Dr. Nagai is remembered as a profound advocate for peace and a symbol of resilience and compassion.
The peaceful world, spreading from Nagasaki
A Pledge for Peace
As a city that experienced the devastation of an atomic bombing, we are committed to appealing to the world about the existential threat of nuclear weapons and to spreading a spirit of global cooperation. We will never cease our call until every nuclear weapon on Earth is eliminated.
Historical Context
The development of these weapons followed the 1938 discovery of nuclear fission in Germany. In 1942, the United States initiated the Manhattan Project, a massive and costly endeavor to create an atomic bomb. While the initial target was Germany, the focus shifted to Japan.
It is sometimes argued that the bombings were necessary to bring a swift end to the war. However, many historians also note that the decision was influenced by other factors, including the desire to demonstrate the project’s success and to establish a strategic position at the dawn of the Cold War. Regardless of the rationale, the human cost was catastrophic and serves as a permanent warning. Our city’s experience compels us to advocate tirelessly for a world free from the shadow of nuclear annihilation.
The Nuclear Age
The nuclear arms race intensified dramatically during the Cold War between the United States and the Soviet Union. This period established the doctrine of nuclear deterrence—the belief that possessing nuclear weapons was the most effective way to prevent their use.
While vast arsenals were built amid high international tensions, robust civil movements emerged advocating for nuclear arms control and disarmament.
Following the end of the Cold War in the 1990s, the nature of global conflict shifted. The primary standoff between superpowers was replaced by more regional, ethnic, and civil wars. This new landscape presents a grave and ongoing challenge: the fear that nuclear weapons could potentially be used in these localized conflicts, by state or non-state actors, making their abolition a more urgent and complex issue than ever.
The Present Situation of Nuclear Weapons
Today, more than 75 years since the invention of the atomic bomb, the global nuclear arsenal has grown to a scale where it could destroy all human life many times over. The number of nuclear-armed states has expanded beyond the original five—the United States, Russia, the United Kingdom, France, and China—to include others. Modern thermonuclear weapons are vastly more powerful and destructive than the atomic bombs dropped on Hiroshima and Nagasaki, presenting a perpetual and catastrophic threat to humanity.