A Central Asian river runs through today's Geo Quiz. The river we've spotted on the map isn't as long or as storied as the Amu Darya. Still, the river we're looking for has a claim to fame. Its Persian name means "sprayer of gold." The river's a valuable source of irrigation for large regions of Tajikistan and Uzbekistan.
It flows past the Uzbek city of Samarkand -- once a busy trading post on the ancient Silk Road. But the river originates across the border in Tajikistan's Pamir mountains.
Its river valley is home to a long-lost settlement.
"I'm now walking in a 5,000-year-old house, in a 5,000-year-old town. I've just rounded the corner, and I'm in the home, stepping over the hearthplace..."
You can hear more from our reporter Mary Kay Magistad as she pokes around this ancient settlement when we reveal the answer...