BIRTHDAYS are usually a time for cake, family and relaxation.

But a senior library assistant at Oxford University’s Bodleian Library has instead decided to set himself the ultimate challenge.

Simon Salome-Bentley of Leafield, West Oxfordshire, is marking the joint celebration of his 65th birthday and retirement from the library by running the London Marathon.

Mr Salome-Bentley, who has worked at the library on Broad Street for 15 years, will retire on Friday, April 5, the day that he is 65.

He will race his brother-in-law Paul Keetley, 60, in the marathon on Sunday, April 13, for Age UK.

The librarian ran the marathon for the first time in 2008 in five hours and 31 minutes.

His brother-in-law, Paul, hoped to beat Simon’s time but was bested by the librarian by just one minute.

This year, the pair will go head to head in the challenge.

Mr Salome-Bentley said: “I started training in October and I now run up to three times a week.

“I’m up to being able to run 13 miles, the distance of a half marathon.

“I would like to beat my time from 2008 but I doubt I will.”

The runner regularly trains in Leafield and so far has been able to avoid running in flood water.

He joked: “The Bodleian staff think I’m a mad to do this.”

After the challenge, Mr Salome-Bentley hopes to spend more time gardening with his wife Nicola.

The Caterham F1 team has given part of the wing of a Formula 1 car to Mr Salome-Bentley. He hopes to auction it as part of his fundraising.

To donate visit justgiving.com/ simon-salome-bentley1