It's a magnificent milestone which many parkrun participants aspire to - totting up one hundred runs.
And one runner, hailed as "a legend" by fellow athletes, has just notched up her century - at the age of 92.
Grandmother Marie Palmer was applauded and presented with a bouquet of flowers, as she crossed the finish line at Brundall parkrun on Saturday.
Her daughter and granddaughter had travelled from Staffordshire to surprise Mrs Palmer by joining her on her landmark laps.
And, in keeping with the landmark figure, Mrs Palmer, who lives in Brundall, came 100th at her 100th parkrun at the village's country park.
Mrs Palmer, a retired laboratory assistant, who used to work at the Norfolk and Norwich Hospital, took part in Brundall's second ever parkrun, in 2015.
She said: "I always used to do a bit of running and when I found out this had started, I decided to join.
"It is so sociable. It's such a friendly group and I do enjoy it... when I've finished!"
Mrs Palmer holds the Brundall parkrun record for 85 to 89-year-olds at 42 mins and 22 seconds, and for 90 to 94-year-olds at 57 minutes 59 seconds.
Saturday's finish was a slightly more leisurely one hour two minutes, although one fellow runner joked that was because she was "milking the applause".
Mrs Palmer used to run the four-lap, 5k course, but, after operations which mean she now has two artificial knees, she walks around these days.
She said that enables her to have a good chat with the tail-walkers - the volunteers who make sure everyone in the run is accounted for.
She said she had got out of the habit of doing the runs after her knee operations and the Covid lockdowns.
But Stuart Harper, event director of the Brundall parkrun, encouraged her to stick with it, even if that meant having to walk the course.
She said: "Stuart kept me going. When I had my knees done I stopped for a bit, but I'm glad I came back."
Mr Harper described Mrs Palmer as "a legend". He said: "She's amazing. She's coming every week, come sun, wind or rain and she's exactly what parkrun is all about.
"It's not all about coming first and what time you get, it's about turning up and being part of the community.
"Marie is so much fun. Everyone loves her and enjoys her being here."
PARKRUN PIONEERS
Fauja Singh, who took up running in his 80s and has completed marathons, was still doing parkruns at the age of 107
Bob Emmerson completed his 400th parkrun at the age of 88, last year in Northampton
Paul Freyne has completed hundreds of parkruns at more than 450 different venues
Great Yarmouth's parkrun course has been ranked as the toughest in the country, with runners following a gruelling course along the town's beach
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