The Secret of Blue Water

Nadia and the Mysterious Sea also known as The Secret of Blue Water is an excellent action-adventure story spanning 39 episodes. The series is very Miyazaki-esqe: it centers around Nadia, an orphan circus performer who wears a strange pendant called Blue Water. She is befriended by Jean, a young inventor and coincidentally also an orphan. Blue Water involves them both in a series of adventures connected with the mysterious Captain Nemo and the submarine The Nautilus.

The story is (very loosely) based on Jules Verne's classic novel 20,000 Leagues Under the Sea, and, I would suggest owes some small acknowledgement to another classic: Castle in the Sky, Laputa.

Nadia looking pleasantly surprised.
Nadia and Jean on Nadia's bike.
Another head shot of Nadia.
Elektra, Captain Nemo's first mate.
Senorita Grandis, the woman who chases Nadia in persuit of Blue Water, and one of her thugs, Hanson.
Artwork featuring Jean with his flying goggles on.
Nadia jumping in her somewhat, ahem!, revealing circus outfit as "Nadia, Queen of the Jungle".