Wikia

Age 761 is a major year in the Dragon Ball universe. It marks the beginning of the Dragon Ball Z era.

Raditz arrives on Earth, informs Goku that he is a Saiyan and his brother, then kidnaps Gohan.
Piccolo and Goku team up and form the Z Fighters.
Piccolo kills Raditz and Goku with a Special Beam Cannon.
Vegeta and Nappa learn of the Dragon Balls and plot a course for Earth.
Piccolo takes Gohan to train, while the other Z Fighters train with Kami and Mr. Popo.
Goku begins to travel Snake Way, but fell down to Hell, and got back up.
Goku meets Princess Snake.
The Capsule Corporation robot C-6 is destroyed as the Nemuria Ruins collapse.
The Orphans are captured and taken away, while Gohan and Pigero escape.

Age 761