Something I and probably a lot of other people who watched it as kids in America, Canada and elsewhere during the 1980's have been long waiting for. Here is the text of the article about it that just apeared on Ain't It Cool News, also US viewers will probably know it as The Seven Cities of Gold:

"Australia's Umbrella Entertainment Studio Pierrot's children epic the Mysterious Cities of Gold on a disc DVD set in August.

Features in the set include
Deleted Scenes
English dubbing cast documentary with the 4 main cast
The dubbing cast recreate a scene featurette
Production documentary with the director Bernard Deyries, the producer Jean Chalopin and the composer Shuki Levy
Phillip Schofield Broom Cupboard Singalong Clip
Karaoke Theme Tune Singalong
Crew Biographies
Dubbing Cast Biographies
Character Biographies
Series Synopsis
Episode Synopsis
Original Storyboards
Original Production Drawings
32 Page Collectors Booklet
12 Page History Booklet

The show aired on American TV on Nickelodeon in starting in 1986."