Programmable computer older than Christianity found in shipwreck

Thought to have been built at the end of the second century BCE, the Antikythera mechanism is considered the first programmable computer. Thanks to an intricate series of gears and dials, the mechanism could be used as a calendar, to track the phases of the moon, and to predict eclipses. It's an object out of time: no other artefact as complex was built during the thousand years after the mechanism's creation--that we know of.

The Antikythera mechanism was named after the shipwreck on which it was discovered. Having sunk to the bottom of the sea in the first century BCE taking the mechanism with it, the shipwreck lay undisturbed until 1900, when a group of Greek sponge divers discovered it and began bringing its treasures to the surface.

After the death of one diver and two others becoming paralysed, operations to recover the artefacts were brought to a halt, but not before statues, ceramics, and the mechanism itself were brought up.