Archaelogists have discovered one of the world's oldest sundials in Egypt's Valley of the Kings.

The 3,200-year-old sundial dates back to 13th century BC, an era when Egypt's19th Dynasty Pharohs ruled. Valley of the Kings is a place where rulers from the New Kingdom period (around 1550 BC to 1070 BC) were buried, reported LiveScience. The sundial was found in an area of stone huts beloging to workmen who were involved in the construction of the graves. 

The sundial could be the world's oldest to have ever been discovered. Prior discoveries of the sundial dates back to the Greco-Roman period which lasted from 332 BC to AD 395.

"The significance of this piece is that it is roughly one thousand years older than what was generally accepted as time when this type of time measuring device was used," said researcher Susanne Bickel, of the University of Basel in Switzerland.

The sundial was made up of a flattened piece of limestone called ostracon with 12 sections drawn on top. Each section had a small dot in the middle that likely helped to observe precise times. The ostracon had a hole at the centre through which a metal or a wooden bolt would have been inserted to cast the sun's shadow and reveal the time of the day.

It is not clear as to what purpose the sundial had served for the workmen. Researchers suggest that the sundial could have been used to envisage the length of the hours and also to measure the work hours. "I wondered whether it could have served to regulate the workmen's working time, to set the break at a certain time, for example," Bickel told LiveScience.

The sundial was found along with other limestone chips at the site. The limestone chips had small inscriptions and workmen's sketches. Archaeologists also discovered a 3,500-year-old tomb with two burials - one from Egypt's 18th dynasty and the other from the 22nd dynasty.

A sarcophagus (wooden coffin) in the tomb was holding the mummy of a woman named Nehemes-Bastet.