Stays at luxury London hotels are a great way to celebrate a special anniversary, but most guests probably wouldn't consider attempting a 26.2-mile run as part of their getaway in the capital.
However, for Chris Robson, 73, and his wife Charm, 72, from St Bees, in Cumbria, it was the perfect way to mark 50 years of marriage.
The couple will be joining thousands of other runners on April 22nd for this year's Virgin London Marathon as part of celebrations for their golden wedding anniversary, a milestone they reached in December.
They will be running to raise money for Alzheimer's Research UK and both already have several marathons under their belts and regularly compete in trail races in the Lake District.
But while Mr Robson has run the London Marathon twice already, it will be his wife's first time.
"We thought around about September, 'well OK, we have never run the London Marathon together so we might as well have a go'," he told the BBC.
"It seemed a good idea and also raise some money for Alzheimer's Research UK."
The pair, both retired teachers, are already well into their training regime and have been clocking up between 30 and 40 miles of running practice a week.
Mrs Robson hopes to complete the marathon in about five hours, with her husband aiming to record a time of around five hours and 30 minutes.
They chose Alzheimer's Research UK as their charity after being affected by the disease as a family, Mr Robson explained.
"It strikes suddenly sometimes, it's insidious, it's awful, it's life changing," he told the news provider.
"The research has been, I think, underfunded. My mother spent the last 15 years of her life really in a sort of grey fog as a shadow of herself. And we felt that this is something that needs support."