The Nile River (Africa) is always claimed to be the longest river in the world with 6,695 km (documented as 6,650 or 6,853 km). In 2007, a team of Brazilian and Peruvian scientists announced that the Amazon River (South America) is more than 100 km longer than the Nile, according to National Geographic. This makes many people wonder which river is the longest. 

However, the Guinness record still confirms the longest Nile in the world. Many other documents also confirm this. According to Livescience, the Nile River consists of two tributaries, the White Nile and the Blue Nile, flowing through 11 African countries including: Tanzania, Burundi, Rwanda, Democratic Republic of Congo, Kenya, Uganda, South Sudan, Ethiopia, Sudan, Egypt and Eritrea. For Egypt or Sudan, this is the lifeline river. Even Egypt is also known as the "Gift of the Nile" because of the great role the river plays in Egyptian daily life and culture. 

 (Source: Collector)