I found a few French media sources that claim the return of Les Mystérieuses Cités d'or or known in the States as The Mysterious Cities of Gold. Appears a production company names Blue Spirit is handling the reigns.
I am thoroughly glad that the character designs and aesthetic of the original show is kept; though the production value has been vastly improved. Gotta hand it to the French; an American production would most likely have "amped-it-up" or give it an "animated-look" a-la the WB. Also I'm am happy to hear that this is not a reboot, but an actual continuation of the original series; taking off after the events at the end of the first series.
media:
http://alpha.heroshock.com/?p=25779#more-25779
Blue Spirit:
http://www.spirit-prod.com/site_bsa/
I grew up watching The Mysterious Cities of Gold on Nickelodeon with my brother in the mid-80's. It was part of a group of Japanese-European produced cartoons that made their way stateside. From the opening music and stylistic Mesoamerican themes, I remember this series fondly. With an over-arching storyline you journeyed along with Esteban, an orphan and so destined "Child of the Sun", from Spain and overseas to the undiscovered land of the Americas. Along the way he is befriended by would-be treasure and adventure seeking mercenaries, Mendoza and his bumbling sidekids, Pedro and Sancho. He would also meet his most trusted friends, Zia, a daughter of a Incan priest, and Tao, the last survivor of the Mu empire.
When they're not running from the Spanish conquistador Pizarro and his men, their adventures lead them to the discovery of wondrous temples and cities, new and different people, and even sun powered machines made of gold.
Had a link to all the episodes on youtube, but looks like the videos have been removed since; here is a link to one of the other shows imported to the states via Nickelodeon we also watched,that was equally intriguing to me as a kid.
Le Monde Engloutis:
01 LES MONDES ENGLOUTIS by djoik