Isabella Mcardle (nee Hawkins) celebrated her 100th birthday with friends and family at St John's Care Home in Melrose on Monday.
She revealed she has never owned a car and continued to climb mountains into her eighties.
The former telephone exchange operator, who was born and bred in the Borders, was the first of two residents at the care home due to mark the milestone this month.
Retired teacher Jean Jamieson, from Ayr, is also set to turn 100 on April 26.
Speaking to the Border Telegraph, Isa, who now walks with the aid of a stick, said: "I never had a car, never drove a car, I never even rode a bicycle. I walked everywhere - that's what keeps me going.
"My favourite walk was up the Eildon way and Gattonside hills. And I enjoyed it."
Isa was born at Cavers Car near Lilliesleaf on April 2, 1912. She worked in the town's telephone exchange where she met her husband, Andrew Mcardle. And her father was the head gardener at the former Hydro, now the Waverley Castle Hotel.
Her neice, Anne Macleod, from Dingwall, said: "She's a true Borderer and has never been away from Melrose."
She added: "On behalf of Isa, we would like to thank everyone for their kindness for coming to enjoy the afternoon and for all the beautiful gifts, flowers and chocolates that we received. We were quite overcome by it all."
Isa and Jean are the oldest residents at the care home in Melrose. Manager Craig Martin, of Mansfield Care, said: "We are very privileged to have two residents who are celebrating their 100th birthdays in the same month. When you look at them you would never imagine they were that old. They are two real characters and have a great sense of humour."
And he added: "Some staff have even come in on their day off to join in the celebrations."