The Oyapock River is a significant waterway located in South America, forming part of the border between Brazil and French Guiana. It flows approximately 500 kilometers (310 miles) from its source in the Tumuc-Humac Mountains to its mouth at the Atlantic Ocean. The river is known for its rich biodiversity and serves as an important habitat for various species of fish and wildlife. The Oyapock River is also vital for local communities, providing a source of water and transportation. It supports fishing and other economic activities for the indigenous populations and settlers in the region. The river's ecosystem plays a crucial role in maintaining the environmental balance in this part of the Amazon rainforest.