O is for Of Sea and Stone
Of Sea and Stone (Secrets of Itlantis) by Kate Avery Ellison
When a ship emerges from the ocean and men burn her village, Aemi is captured and enslaved below the waves in Itlantis, a world filled with ancient cities of glass and metal, floating gardens, and wondrous devices that seem to work magic.
Desperate to be free, Aemi plots her escape. But the sea holds more secrets than she realizes.