The 59-year-old has retired as the States of Guernsey head of heritage services.
He said it had been a wonderful experience, but a steep learning curve.
‘I have quite a big heritage background, but I knew next to nothing about fine art and little about conservation,’ he said.
‘It’s been a constant learning process. My staff were always working on projects and coming up with new ideas. So it’s been very exciting.’
When Dr Monaghan took on the post, fewer people were visiting the sites.
‘We put our minds to how to turn things around,’ he said.
The museums team began to do targeted exhibitions, such as tourist displays during the summer months, but then more niche exhibitions, aimed at locals, during the shoulder months, such as photography.
Events were also increased. The introduction of the £18 season pass – known as a Discovery Pass – boosted numbers.
‘We did have season tickets, but not many people used it,’ Dr Monaghan said.
‘We thought if we halved the price, we would sell twice as many. We actually sold four times as many. Each Discovery Pass is used five times a year, so that has done a lot for repeat visits. We have seen growth in the number of people coming back. Actual footfall has gone up by 50% [since 2006].’
Dr Monaghan has overseen the four-year overhaul of museum storage, as well as the creation of the RGLI museum and the Royal Guernsey Militia museum.
‘There’s always more you could do,’ he said. ‘I was tempted to keep on until the next project is done, but then there would always be the next project.’
He said his team would always face the challenges of tight budgets and preserving history, whether that be fading paintings or crumbling forts, as well as the changes in technology. ‘We need to move with the times,’ he said. ‘It’s very easy to do what you did last year, but it’s brave to stop doing that and do things differently.’
Originally from Yorkshire, Dr Monaghan met a Guernsey girl at university and moved to the island in 1985 to work on the Roman wreck project. After four years he moved back to the UK to work as a Roman pottery researcher. He returned in 1993 and worked in finance until 2006 when he got the job of museums director.
‘This has been the best job of my life,’ he said.
He said his biggest regret was that Asterix – the Roman wreck – was still not formally on display, although it can be viewed at Guernsey Pearl.
He is now moving back to Yorkshire, but will be back regularly for events.
Former historic sites curator Helen Glencross is now the acting head of heritage services.