Itacoatiara, Amazon

I've reached an island with Paraná da Trinidade (stream) to the north and the Amazon flowing to the south. I hopped off here, tossed my daypack on, filled it with plenty of water and snacks and walked along its shoreline for the next 6mi (10km). This is a river island, and it is one of a great number of river islands found in the Amazon. Some are nearly as large as a small country or a US state. For instance, Ilha Tupinambarana, which I will pass by later, is about the size of Connecticut.

These river islands are formed when sufficient sediment deposits known as alluvium build up. This alluvium is a mixture of clay, sand, gravel, and other organic and inorganic matter carried downstream by the river and then deposited on the riverbed. When the alluvium gathers mass, it protrudes from the water creating a small sediment island. The alluvium is rich in nutrients and minerals, making it fertile soil for agriculture and plant growth. Grasses are the initial colonisers providing stability to the island, which is then succeeded by woody vegetation that later turns into a forest.

The shape of these islands constantly changes because of the river's powerful currents and seasonal flooding. Many of them are uninhabited, left largely untouched by human activity, providing a haven for rare and endangered species. In contrast, the few inhabited islands are often used for agriculture, fishing and hunting, giving food and water to local communities.

As I reached the end, appreciating the sights and sounds along the way, I reboarded the riverboat for a short trip to Itacoatiara.

Located on the left bank of the river, Itacoatiara is one of the region's main commercial centres, with a port responsible for cargo transportation in Amazonas. It is known for its production of timber, as well as fishing and agriculture. The city was shaped by native Brazilians, early European settlers, and Africans. In modern times, immigrants from Japan, Syria, Lebanon and Morocco added to the cultural melting pot.

With a festival event that includes music, dancing and a beauty pageant, the city celebrates the local fruit, cupuaçu. It is a melon-sized, hard-shelled fruit with a creamy white pulp that tastes like a mix of chocolate and pineapple, with a hint of banana or pear. It is a sister plant of cacao and is often used in desserts, drinks and flavouring of other dishes.

I took a short stroll along the coast and came across a residence bound by a high fence painted with stunning sceneries of the Amazon River featuring giant waterlilies, a jaguar, a toucan, a macaw and a native girl.

After wandering around the city centre, I boarded the riverboat and continued my cruise.