Many traders met on the Silk Road. It was an ancient system of roads and trading posts.

It linked Asia with regions along the Mediterranean Sea.

The country we today know as Afghanistan was in the center of the Silk Road.

Afghanistan has many large mountains. These actually helped ancient traders travel, says Dr. Fredrik Hiebert. He is a National Geographic Society archaeologist. Archaeologists study objects from long ago.

All those mountains mean there are valleys. These are like natural trails. It was easy for traders to follow along the valleys and rivers, says Hiebert.

Graveyard Of Empires

Afghanistan sits between the China Sea and Mediterranean Sea. People from Asia, eastern Africa and southern Europe all met there.

Afghanistan's location on the Silk Road helped it gain great wealth. It had many farming products, minerals and animals to trade, Hiebert says.

More than goods were traded. Ideas were exchanged on the Silk Road, too.

Buddhism, for example, started in India. It spread to Afghanistan before moving to China, Hiebert says.

Bamiyan is in central Afghanistan. It was a center for the religion Buddhism. The area had statues of Buddhas that were 60 to 90 meters (200 to 300 feet) tall. They towered high up on cliffs. These were easy for traders to see, Hiebert notes.

The statues were destroyed by the Taliban in 2001. The Taliban is a violent extremist group. It is fighting the government to control the country.

Traders also shared ideas about art. Evidence of Greek building style was found in ruins in northeastern Afghanistan. Messages to Greek gods have been found on ancient objects there.

Afghanistan's wealth also made it a target. Other empires hoped to take it over.

Still, Afghanistan has been nearly impossible to conquer. Alexander the Great could not take it. The British Empire could not take it in the 1800s, either.

Afghanistan is "really cold in the winter," says Hiebert. It is also "really hot in the summer."

The area's weather and mountains also have divided Afghan people.

Mountains block off groups from one another. When groups meet in the valleys, there is sometimes fighting, Hiebert says.

New Silk Road

For the past 30 years, Afghanistan has been torn apart by war. Still, Hiebert says, Afghanistan has lasted for 5,000 years. He thinks it can survive once the country becomes stable again.

Large amounts of underground copper were just found there, he says. Hiebert wonders if another Silk Road could happen.

Hiebert thinks that old trade partnerships could be renewed soon. However, silk will not be traded, he says. Oil and gas will be.

Still, Afghanistan faces much trouble. It could take many years to heal from it, he says.