Ostia is a coastal settlement in Leva Bay, Po-Wahi, and home to the Po-Koro Naval Division.
Ostia sits prominantly on the coastline of Leva-Bay with its white-washed buildings rising up the cliffside to the desert. A great tower of white stone cuts through the town of cramped row houses and winding stairways like the prow of a ship through rough waves, home of Ostia's government with prisons in the bowels. The shipyards are full of the clamor of shipwrights and sailors as Po-Koro's navy is assembled. In truth Ostia is a recent village blossoming under the watchful eye of the Po-Koro Sentinels and capital of northern oceanic trade for the island of Mata Nui.
- Akiri Hewkii commisioned the construction of Ostia upon his election as leader of Po-Wahi, hoping to turn the sleepy fishing village and trading post in Leva Bay into something more profitable and supportive. In a fairly short amount of time, three months, the village and grown along the waterfront and the main tower of Ostia had been constructed.
- After a deal for timber with Akiri Kongu, Hewkii sent a shipment of lumber to Ostia and the Po-Koro navy came into being as ships were construted for the purposes of trade and plying the waters for piracy.
- A criminal escaped from the prisons of Ostia's tower, leaving clues followed by Kale Ironshaper the crew of the Infernavika.
- Ostia was created during the 2013 Arc (Book 2, Chapter 1), by Kughii for Lloyd: The White Wolf.