Harka Nui was a tropical island about 50 kilometers away from Metru Nui. 500 years before the Great Cataclysm, two Matoran named Eika and Ryusho were transformed into Toa. 300 years later, the Visorak invaded and the Matoran escaped the island. There has been no sign of them since then, but rumors say that the Matoran have built a floating city somewhere in the sea.