Wikipedia
Marajó
Marajó is an island located at the mouth of the Amazon River in Brazil. It is part of the state of Pará. Marajó is the largest fluvial island in the world, and the second largest island in South America. With a land area of Marajó is comparable in size to Switzerland. It is approximately long and wide.
The island is known for the pororoca, a tidal bore phenomenon in the river that creates large waves reaching in height. It is a tourist destination, especially among surfing enthusiasts.