Which is the longest river in the world that flows entirely within one country?

all knowledgeable questions I Learn a lot. Wow

To build the dam many people had to loose their homes, we witnessed the destruction of villages on cruise trip. The rubble from the homes was used in the dam construction. It was sad to see, a lot of locals were begging on the streets, many were disabled. Tragic the price many had to pay for the dam to be built. Plus the Yangsee dolphin is now extinct due to water pollution.

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