Cynthia Playford has inspired thousands of people with the flora and fauna of Kings Park for the past 30 years - and she shows no signs of slowing.
The 78-year-old is an original member of the Kings Park Volunteer Guides, who this month celebrate their 30th anniversary.
She said visitors were grateful for the guides' insights on the history and biodiversity of the park.
"People are often amazed and say how grateful they are to have had things pointed out to them that they never would have noticed if they were walking around on their own," she said.
The program has grown to about 120 guides, who offer two to three free tours daily.
Mrs Playford said the main difference over 30 years was the advance of scientific research and the new information it made available to visitors.
"There's so much more information than there ever was in the beginning because we've got this fantastic science department in Kings Park," she said. "They've produced world-class research."
Paola Vallesi, in her first year as a guide, said the strength of the program was in the learning.
"It is about the more experienced guides really teaching the younger guides, it's a real friendship," she said. "People can take themselves on a walk anywhere but when they've got a guide taking them they just learn that little bit extra."
Mrs Playford said she remembers going to Kings Park on school trips from her home town of Coorow. "Coming down from the country, we were always driven up to Kings Park to see the lights of Perth," she said.