Australia’s oldest set of twins celebrated their 100th birthday in Perth today.

Identical twins Flora Barrett and Winifred Hopes were born to a large farming family at Harvey, in WA’s south west, in 1913.

They have lived through the Great Depression and two world wars.

Today the sisters opened letters from dozens of dignitaries, including the Queen, the Prime Minister and the Governor General.

Between them, they have 15 children, 36 grandchildren, 72 great grandchildren, and 19 great great grandchildren, some of whom joined them at today’s celebrations.

Winifred, who had two sets of twins herself, says an active life including dancing, bowls and tennis had helped her reach the milestone.

“I don’t feel 100, I only feel about 20,” she said.

Her secret to a long and healthy life: “Don’t smoke, don’t drink and don’t go out with bad men, that’s the secret”.

Flora says she has had a very happy life despite a difficult start while growing up in the country.

“Had to struggle in the early days,” she said.

“Was lucky to wear a pair of shoes on our feet when we were young, things were that bad in the early days.”

Both women say they have lived a happy life with no regrets, and there is still a few years left in them yet.

Previously, South Australian twins Gene and Dorris Clarke were the eldest when they died in 2012, aged 101.