- Chalcolithic (Wikipedia)
The Chalcolithic (also called the Copper Age and Eneolithic) is an archaeological period characterized by the increasing use of smelted copper. It follows the Neolithic and precedes the Bronze Age. It occurs at different periods in different areas, and is absent in some parts of the world, such as Russia. Stone tools were still predominantly used during this period.
- Nile (Wikipedia)
The Nile (also known as the Nile River) is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa. It has historically been considered the longest river in the world, though this has been contested by research suggesting that the Amazon River is slightly longer. Of the world’s major rivers, the Nile is one of the smallest, as measured by annual flow in cubic metres of water. About 6,650 km (4,130 mi) long, its drainage basin covers eleven countries: the Democratic Republic of the Congo, Tanzania, Burundi, Rwanda, Uganda, Kenya, Ethiopia, Eritrea, South Sudan, Sudan, and Egypt. In particular, the Nile is the primary water source of Egypt, Sudan and South Sudan. The Nile is an important economic driver supporting agriculture and fishing.