The Flintstones

 April 1, 1966, the final episode of The Flintstones aired on ABC.

Produced by Hanna-Barbera, the series originally premiered on September 30, 1960, and became the first animated show to successfully air in prime time. Set in a whimsical Stone Age world, it followed the lives of Fred and Wilma Flintstone and their neighbors and best friends, Barney and Betty Rubble, blending prehistoric settings with modern-day suburban life.

The show’s enduring appeal came from its clever contrast of contemporary issues in a prehistoric setting. It remained the most successful and longest-running prime-time animated series for decades, until The Simpsons surpassed it after debuting in 1989. In 2013, TV Guide ranked it the second-greatest TV cartoon of all time.