Casey Kasem's American Top 40 was the forerunner to today's American Top 40 countdown. It was the original nationwide syndicated Top 40 countdown. The first countdown aired in 1970. Casey Kasem took a break from 1988 to 1995, but returned from 1998 through 2004, when Ryan Seacrest took over the AT40 countdown, bringing it to its present forms.

Casey Kasem's AT40 countdown episodes are chock full of good music from the best decades of American music! From Kasem's first words — which lure listeners in immediately — to the closing jingle, you'll enjoy every minute!

The original AT40 was unlike any countdown still going today — with replays of classic oldies hits, "Long Distance Dedications", and small music trivia, it was an extremely well-rounded show full of great talent and voice. You can read more about the original AT40 on Wikipedia.

Many radio stations, such as WRIT FM 95.7 in Milwaukee, air replays episodes of "Classic American Top 40" (as they are called) on a weekly basis; WRIT airs them Sundays from 9am-12am, right after the Beatle Brunch (8am-9am). All in all, that's four hours of great music right there! Usually the replays are from the late 70s or early or mid-80s, right at the peak of the AT40 era.

You can also listen on demand. Many AT40 episodes have been digitally remastered and are now available for sale on CDs; in fact, if you listen to an aired replay of AT40, you'll hear at the end a small announcement that "this episode of Casey Kasem's American Top 40 was digitally remastered by…" — you can buy those same episodes and listen to them commercial-free! If you'd just like to listen to the show without the music, many are also available on YouTube!

Here's some links and more information: