Pippa Middleton scales Sydney Harbour Bridge on honeymoon

Newly married James Matthews and Pippa Middleton. (Getty Images)

Pippa Middleton and husband James Matthews have scaled Sydney Harbour Bridge during their honeymoon.

The 33-year-old - who is the younger sister of the Duchess of Cambridge - married her 41-year-old partner in a traditional ceremony on May 20, and the pair have enjoyed some time relaxing in French Polynesia before they jetted off to Australia to continue their romantic getaway.

And according to The Express Online, the brunette beauty and the dark haired hunk - who is the older brother of former 'Made In Chelsea' reality star Spencer Matthews - were spotted pulling on a blue boiler suit and safety harness before they climbed 440 feet up to the top of the tourist attraction one evening to admire the views.

It has been reported the newlyweds have made sure they remained active during their vacation as it is rumoured they have enjoyed morning runs with one another through the Botanical Gardens in Australia.

And it is believes Pippa and James will continue their travels and will be heading to New Zealand next to extend their trip.

Although the party planner has visited a number of places during her honeymoon, as she first arrived in Los Angeles en route to the Pacific Islands, they were keen to enjoy time being "totally alone together".

Speaking previously, a source said: "Pippa and James have loved all the excitement about getting married - but obviously it became a very intense few months and they both feel they're ready to be totally alone together.

"The Polynesian villa is everything people would expect - miles of white sand, beautiful scenery and a 24-hour-a-day service from staff - and they're staying there for a week.

"No expense was spared on lavish bravado for the wedding, but the honeymoon plans are totally different. They're quiet, peaceful and romantic."