The Amazon Delta ( Portuguese: delta do Amazonas) is a huge river delta formed by the Amazon River and the Tocantins River (through the Pará River distributary channel), in northern South America. [1] [2] [3] It is located in the Brazilian states of Amapá and Pará [4] and encompasses the Marajó Archipelago, whose largest island is Marajó Island. The main cities located in the vicinity are Belém and Macapá (both with their respective metropolitan regions). [5]