Pathfinder — Julie Bertagna

Less than a hundred years from now, the world as we know it no longer exists. Cities have disappeared beneath the sea, technology no longer functions, and human civilization has reverted completely. Only Mara has the vision and the will to save the people of her drowning island as they search for a new home-her hope bolstered by information from a young revolutionary she met online in the last vestiges of the internet. His home, the sky city of New Mungo, is their only option. Can Mara find her way to him and give her people one last chance at survival?