Clay tablets dating back 4,000 years show the beginning of writing and literacy in ancient Anatolia, in the middle of modern-day Turkey, according to researchers.

Excavations in the province of Kayseri, southeast of Turkey's capital Ankara, at an ancient settlement or burial mound shed light on writing from around the year 2000 B.C., said Fikri Kulakoğlu, a professor of archeology at Ankara University and head of the excavation team.

In 70 years of excavations at the Kültepe settlement, 25 kilometers (15.5 miles) northeast of Kayseri, some 23,000 cuneiform-script tablets have been found.

"These are the first written tablets in Anatolia. Anatolian people learned how to read and write in Kültepe. The first-ever literate people in Anatolia are from Kayseri," said Kulakoğlu.

Many of the tablets excavated are exercise tablets, apparently used by children to practice their writing.

The reading exercises in scripted tablets are signs of school-like instruction, he said.

Ancient day traders

Alongside the practice tablets are ones used for trade or business, Kulakoğlu said.

The tablets were used to record anything "valuable," he explained.

"These tablets show that local merchants made their presence in Anatolia alongside the Assyrians," who come from a civilization in ancient Mesopotamia, he said.

Kulakoğlu added that the clay tablets excavated from Kültepe are among the rarest in the world.

Kültepe has been a candidate for the UNESCO World Heritage List since 2014.

According to UNESCO's website, the site of Kültepe was the capital of the ancient Kingdom of Kanesh and center of a complex network of Assyrian trade colonies in the 2nd millennium B.C.