0100 GMT January 23, 2021
Clarissa Greenfield, of Ashby-de-la-Zouch, Leicestershire, the UK, was applauded by neighbors as she finished on Sunday, BBC reported.
The schoolgirl, who logged the distance over 10 days to stay within lockdown guidelines, has so far raised £1,000.
"I'm hundred percent tired — there was a massive big hill at the end which was really bumpy," she said.
"But it was really nice to see everyone clapping — my friend was there and all my family."
She started fundraising in 2015 after her grandma Denise Mansfield, from Swadlincote, had surgery at Birmingham's Queen Elizabeth Hospital for two brain aneurisms.
Since then she has organized a Christmas market, donated hundreds of Easter eggs and started a postcard scheme which has seen cards sent to her from all over the world.
She had planned to cycle a 26-mile marathon but decided not to because of the lockdown restrictions.
Instead she started cycling 10 miles every day on May 1 and finished at her house on Sunday.
Her mom, Felicity Greenfield, 25, said: "It's just amazing. She was not going to be stopped by the coronavirus lockdown.
"A few years ago to me, if everyone did one nice thing a day the world would be a better place. And that's true, even if this is quite a big thing.
"My mom really appreciates it, and Clarissa can't wait to give her a hug."