First known computer, Pt 1              Worksheet     Video

Now we tend to think of computers as being a fairly recent invention. But the world’s oldest-known computer is actually a few thousand years old. It’s called the Antikythera Mechanism.

We discovered it by total accident. Just before Easter in the year 1900, two small boats were sailing back from North Africa to their home in Greece. They were sponge-fishers - six divers and 22 oarsmen. They were using one of the ancient shipping routes between the Eastern and Western Mediterranean. They were really close to home, between the islands of Kythera and Crete. And then they ran into some gales and squalls.

So they sought shelter in a little cove off the tiny, rocky and mostly barren island of Antikythera. They had never been there before, so after the storm had gone they took a peek. To their surprise, they saw an enormous 50-metre-long wreck of a Roman merchant ship, about 42 metres below the surface. And even though it had been there for more than 2,000 years, they could see valuable bronze and marble statues poking through the sandy ocean floor.

They returned with a Greek naval ship. This was a major discovery in the field of underwater archaeology. It took a year and a half to finish the excavations – in September 1901.

Six months later – in May 1902 - reports began to surface of a strange machine being found on the sunken ship.

And it was more than half a century before we began to understand what this machine was about. In 1959, the journal Scientific American published an article entitled, “An Ancient Greek Computer”.

Basically, it was metal device housed inside a wooden box - roughly the size of your average shoe box. It was a complex set of more than 30 metal gears, operated by turning a small crank handle on one side. And in response, metal pointers would begin to slowly spin on three separate dials – one on the front, and two on the back.

These dials could tell you the future - where the Moon and the Sun would be in the sky, when various major games such as the ancient Olympic Games would happen, the phases of the moon – and amazingly, when both solar and lunar eclipses would happen.

This device - some 2,200 years old - is the oldest known computer. It’s an analog computer - not a digital computer - but it’s still a computer.

We have no idea who built it. It is so advanced, that nothing equalling it would be built for another 1,500 years. We also have no idea how they were able to gather the data needed to predict eclipses. And before this discovery, there had been zero evidence that the ancient Greeks possessed scientific instruments and fine mechanical objects.

We have found a scientific object older than the Antikythera Mechanism: a 3,600-year-old artefact called the Nebra Sky Disk. It’s a bronze disc - weighing 2.2 kg and about 30 cm in diameter – and it was found near Nebra, in Germany. It’s inlaid with gold symbols (and curiously, the gold came from Cornwall in south-west England, far, far away). The gold symbols include depictions of the full moon, the crescent moon, and a cluster of the seven stars known as the Pleiades. It could have been a guide to the seasons, advising you when to plant seeds.

In early March, the new moon is close to the Pleiades, meaning the beginning of spring. And in middle October, it's the full moon that is close to those stars, warning you of the beginning of autumn. But this Nebra Sky Disc had no moving parts.

Now some people jokingly claim that Adam and Eve had the first computer – an apple. But all it took was just one byte (that's B Y T E not B I T E), and then everything crashed. Boom boom.

Anyhow, I'll stick to the facts, and so next time I’ll tell you more about this strange set of Gears from The Greeks - the Antikythera Mechanism.


1.    What is the name of the world’s oldest computer?

2.    When was the oldest computer discovered?

3.    How long had the ship been on the ocean floor?

4.    When was the article “An Ancient Greek Computer” published?

5.    How was the Antikythera Mechanism operated?

6.    What was the Antikythera Mechanism used for?

7.    How old is the Nebra Sky Disk?

8.    In what way is the Nebra Sky Disc different from the Antikythera Mechanism?



sought shelter




crank handle



Summary. In about 300 words summaries the main points of Dr Karl’s talk.