The Flintstones (1960-1966)
The first prime-time animated series.

Astro Boy (1963-1966)
Considered by many to be the first anime.

Scooby-Doo, Where Are You! (1969-1970)
The origin of the "mystery gang" that inspired numerous other works and adaptations.

Looney Tunes and Merrie Melodies (1930s-present in various formats)
These Warner Bros. shorts and characters became foundational in American animation.

The Jetsons (1962-1963, 1985-1987)
A futuristic counterpart to The Flintstones centering on space-age technology.