Caviana

Caviana (Portuguese: Ilha Caviana, formerly in Aruã language: Uyruma) is a coastal island in the Brazilian state Pará. The island is part of the Amazon Delta. In the 17th and 18th Century it was the stronghold of the Aruã people. From the island a tidal bore called the pororoca can be observed. Between 1845 and 1850, a strong pororoca split the island into two parts, called Inner and Outer Caviana.