Hiroshima.

The story of the bombing of Hiroshima is about the first use of atomic weapons in war, and the destruction of an entire city:

The bombing
On August 6, 1945, the B-29 bomber Enola Gay dropped the atomic bomb "Little Boy" on Hiroshima, Japan. The bomb destroyed most of the city, killing an estimated 140,000 people.

The aftermath
The bombing caused a heavy downpour of radioactive black rain, contaminating the area. Many survivors later developed cancer, leukemia, and other radiation-related illnesses.

The surrender
Japan surrendered to the Allies on August 15, 1945, six days after the bombing of Nagasaki. The Japanese government signed the instrument of surrender on September 2, effectively ending World War II.

Here are some other details about the bombing of Hiroshima:
The bomb had an explosive yield of 15,000 tonnes of TNT.

The bomb was dropped by Colonel Paul Tibbets, the commander of the 509th Composite Group.

The plane's nose was painted in honor of Tibbetts' mother.

The crew was given cyanide pills in case they were captured.

Nagasaki.

The bombing of Nagasaki on August 9, 1945 was the second atomic bombing of a Japanese city during World War II:

The bomb
The bomb, codenamed "Fat Man", was dropped by a USAAF B-29 plane named "Bockscar". It weighed 10,000 pounds and had a diameter of 60 inches. The bomb exploded at an altitude of 1,650 feet, detonating almost exactly between the Mitsubishi Steel and Arms Works and the Mitsubishi-Urakami Torpedo Works.

The aftermath
The bombing killed between 40,000 and 75,000 people immediately, and another 60,000 were severely injured. The city was destroyed, with houses, buildings, and wooden columns partially destroyed or completely burned down.

The response
The Japanese government issued a statement on August 10, agreeing to accept the Allied surrender terms. Japan surrendered to the Allies on August 15, and the war effectively ended on September 2.

The legacy
The bombings of Hiroshima and Nagasaki remain the only use of nuclear weapons in an armed conflict. The effects of radiation injury from the bombings continued to mount for decades, with long-term effects including cataracts and cancer.

Thx for reading!