Rivers are the birthplace of human civilization. In order to protect and care for the world's rivers, since 2005, the United Nations has designated the fourth Sunday of September every year as World Rivers Day. This international day of observance, aimed at raising public awareness of the value and threats to rivers, is even more relevant today in the context of global climate change and increasing pollution. Here are some of the world's rivers that gave birth to civilizations.

The Nile is the longest river in the world with a total length of 6,650 kilometers. The Nile is not only associated with Egypt, it travels through many countries. The Nile is also known for its abundance of wildlife, such as the Nile crocodile, one of the largest reptiles in the world. Since ancient Egypt, locals have been full of affection for the Nile. Because when the river receded, it would leave a fertile soil for the ancient Egyptians to grow crops and food. The ancient Egyptians and Greeks regarded the Nile as a mysterious river because it flows from south to north and is always flooded during the hottest part of the year.

The Amazon River is famous for its surrounding rainforest. The Amazon River is made up of hundreds of channels and has a total length of 6,400 kilometers. The Amazon River flows through the largest tropical rainforest in the world - the Amazon rainforest. The Amazon rainforest covers an area of 5.5 million square kilometers. It was home to 500 primitive tribes, about 50 of which never interacted with the outside world. In addition, the Amazon River is home to the world's rarest Amazonian dolphins. The dolphin is nearly two meters long and is pink in color, depending on the color of the waters in which it lives. The darker the water, the pinker the dolphins are.

The Congo River is the fifth longest river in the world and the second longest in Africa. There are 32 great waterfalls along the Congo River, including the famous Inca Falls. The Congo River is rich in fish resources, with 686 known species of fish, 80% of which are unique in the world. A species of elephant-trunk fish in the Congo River communicates with each other by means of electricity-generating organs in their tails.

The Ganges originates in the Himalayas and flows through northern India to the Bay of Bengal. 80% of the Ganges River basin is in India, and it also flows through Nepal, China and Bangladesh, with a total length of 2,424 kilometers. The Ganges is the holy river in the hearts of Indians. Indians regard the Ganges as the "mother river".

The Rhine is 1,207 kilometers long and passes through six European countries: Austria, France, Germany, Liechtenstein, the Netherlands and Switzerland. The Rhine is one of the most beautiful rivers in Europe. Among them, the Loorle Reef in Germany has been designated as a World Heritage Site by UNESCO. But the Rhine was heavily polluted in the 1950s and 1970s, causing fish to disappear. After strict sewage restrictions and cleaning, now the Rhine has regained its beauty.

The 2,850-kilometer Danube originates in Germany, flows through 10 European countries, and finally flows into the Black Sea. The Danube Basin feeds 83 million people in Europe and provides drinking water for 20 million people. The importance of the Danube can be seen. The Danube Delta is a paradise for wildlife lovers and bird watchers. 300 species of wild animals live here, including cormorants, white-tailed eagles and ibises. In addition, along the banks of the river there are wild cats, foxes, wolves, and occasionally wild boars or deer.

The Thames is the most important river in Britain. Although it is only 346 kilometers long, it has been an important trade route since ancient times. Goods from all over the world move in and out of the UK from here. There are 45 locks on the Thames, which allow boats to move unhindered on the river when the river falls. Before the 19th century, the Thames would freeze in winter. Back then, there would be frost festivals on the Thames, people dancing and even ice skating on the river.