An 85-year-old has "triumphed" after being awarded a PhD to honour his lifetime of historical research.

Retired engineer Alastair Maxwell-Irving spent decades studying historical architecture in his spare time - and is now thought to be the oldest person in Scotland to be awarded a PhD.

He is Glasgow Caledonian University's oldest graduate, after becoming a Doctor of Philosophy, and passed his PhD viva just days after celebrating his 85th birthday.

Dr Maxwell-Irving, who owns more than 2000 reference books, received the award in recognition of his lifetime of research and two books on the history of the Tower Houses of the Scottish Borders.

READ MORE: University of Edinburgh: ‘Game-changer’ new method could make coronavirus testing 20 times cheaper

The recent PhD graduate, of Blairlogie, Stirling, first graduated from the University of London in 1957 with a degree in mechanical, electrical, and civil engineering and worked for Weir Pumps before retirement in 1991.

Speaking of his recent achievement, he said: "People ask me what I'm going to do with a PhD at 85-years-old but I have plenty of other projects to keep me occupied.

"It is the culmination of many years of research on a subject that has fascinated me since childhood.

"I love the countryside and for years spent most of my weekends visiting sites, photographing them, and taking notes - through summer, winter, snow, and sunshine.

"Everyone at GCU has been so helpful, I can't thank them enough. The award is truly an honour."

Alistair served as an honorary assistant with the Royal Commission on the Ancient and Historical Monuments of Scotland in his spare time for more than 40 years.

His books focus on the historic tower houses of the Scottish Borders, many of which date back to the 14th and 15th century.

Professor John Lennon, Dean of GCU’s Glasgow School for Business and Society, said: "Achieving a PhD at any age is a triumph but this is a truly exceptional case and reaffirms our view that higher education should be accessible to all irrespective of age or any other factors.

"We are so pleased Dr Alastair Maxwell-Irving chose GCU and my thanks to the supervisory team and academics involved in this noteworthy process. Heartfelt congratulations from myself and all at GCU.”