Pichu

This is one of the first drawing I colored with Photoshop, certainly in 1999 or 2000

Here is Pichu, from an oooold cartoon which had a lot of success in France in the 80's.
I don't know the english title, but in french, it's : "Les Mystérieuses Cités d'Or" which means : the Mysterious Cities of Gold...

It's about the adventures of three kids, Esteban, Zia and Tao in Central America in the 1500's, looking for the Cities of Gold.
So if you recognize this cartoon, can you tell me its name in english please ?

Thanks ^^