Edinburgh's oldest volunteer has revealed her secret to long life as she celebrated her 100th birthday.

Doris Keir still actively volunteers at the Northfield and Willowbrae Community Services Group every Monday, where she pours the tea, hands out biscuits, collects donations and offers support to people suffering from dementia and memory loss.

The former council worker marked her centenary on Wednesday at a special birthday party thrown by the Lord Provost of Edinburgh in the City Chambers.

Ms Keir, who still lives independently, said: "It was lovely to visit the Lord Provost and see the City Chambers, which I've never been to before.

"I've been a volunteer for 35 years and I've enjoyed it. When I retired, I thought I have to do something with myself. It has been worth it and if I wasn't volunteering, I'd be sitting at home and that would be boring."

Born in Merchiston, Ms Keir was brought up in Colinton and attended James Gillespie's junior and senior schools, where she was in the same class as author Muriel Spark.

Speaking at her party, she put her longevity down to leading an active life and drinking six glasses of water a day.

She added: "I like seeing everyone from the service centre every week, and if anyone is off unwell I like to ring them up and make sure they are okay.

"I've been volunteering so long now, I might as well keep going until I drop."

Edinburgh's Lord Provost Frank Ross said: "Doris is an inspiration to us all and a formidable champion for those suffering from dementia and memory loss in her community.

"It is people like her who actively make the city a better place to live, and help to inspire more Edinburgh citizens to start volunteering for the benefit of others.

"I am so pleased to be able to show the city's appreciation and pride in her many years volunteering, particularly on this very special birthday.

"My thanks and congratulations on behalf of everyone Doris has helped over the years."