We're heading to a city along the Niger River for today's Geo Quiz.

This city is in Mali.

It was founded by fishermen in the 7th century.

It later became one of Western Africa's important trading centers -- doing a lot of business with other centers, such as Timbuktu.

The city then became the capital of the Songhai Empire in the 11th century. That's when this city really thrived.

Merchants went there to buy and sell everything from gold and copper, to salt and -- sadly -- slaves.

Street scene in Mali: http://commons.wikimedia.org/wiki/User:Guaka

The city went into decline after the 16th century. But you can still take a ferry up the Niger River to Timbuktu.

So, can you name this city in eastern Mali?

We'll be back with the answer -- and music from Mali's Habib Koite -- here...