THE official timekeeper at Blenheim Palace is preparing himself for the daunting challenge of changing 30 priceless historic clocks ready for the end of daylight saving time.

Julian Newman, the palace’s timekeeper, will have to complete the task and change the clocks, including one that is twice the age of London's Big Ben, before 2am on Sunday, October 30.

The timekeeper, who has worked at the Woodstock stately home for more than 12 years, changes the clocks twice annually alongside his other duties of maintaining and repairing the rare timepieces.

He said the worst case scenario would be getting distracted and 'losing track of the time'.

He said: “When the clocks go back, it is a case of stopping each clock then going back exactly 60 minutes later and starting them up again.

“I find it best to do this very early in the morning before the staff arrive, as you can easily get tied up with other events and the last thing you want to do is lose track of the time.”

There are 30 clocks located in and around Blenheim Palace that need to be changed. Two of the most appreciated clocks sit in the Great Hall: a regulator by John Shelton with a grid iron pendulum and one by John Holmes with a glass pendulum.

Among the priceless antique timepieces he’ll need to change is the 18th century East Courtyard Clock Tower, made by Langley Bradley in 1710.

Mr Newman’s favourites are a trio of grandfather clocks which are also located in the Great Hall, one of which chimes every quarter-hour.

He said: “I am fascinated by the intricate mechanisms within this particular clock. When I open the door to wind it you can see the weights for each of the three chimes and the pendulum in full working order.

“Recently the Boulle pedestal timepiece in the third State Room was taken away for repair and we discovered the original winding key hidden all the way at the bottom of the casing. It has probably been there for at least 50 years.”

The palace once operated on its very own ‘Blenheim Time’, introduced by the 4th Duke of Marlborough and used right up until the 19th century when Greenwich Mean Time became universally adopted.

The Duke, an amateur astronomer and close friend of King George III, who himself had a great interest in all things scientific, was given a telescope by the king which he used to determine time throughout the palace, its grounds and the estate.

Blenheim Time was set by the complicated use of a sundial combined with the specific longitude of the palace. Due to the proximity to London, the palace would have been approximately five-and-a-half minutes slower than GMT today.

The Duke would set the time by the regulator grand clock in the Great Hall and all watches were set accordingly.