The world's at your fingertips

One of my favourite bits about writing books is doing the research to build or rebuild the world the characters lived in. From reading the histories of Tacitus or Caesar to try to get a handle on the thought processes in ancient times or the rhythm of their speech patterns, to discovering how they baked bread, carried their swords or wore their clothes; every little item of information can add that little touch of authenticity that makes all the difference.

There are two different types of research: research on the ground and research of the historical sources. When I wrote my first book, Caligula, I did a huge amount of reading to immerse myself in the Roman world, but the physical Rome I built was constructed from a map I discovered on the internet. I only visited the forum properly for the first time when the book was complete and it was wonderful to find that the scale and the topography was just as I imagined it. Claudius was different, because it meant taking vague snippets of information about a battle and recreating something close to the reality using all the military sources I could lay my hands on. The Colchester of Hero of Rome was the first time I was able to actually visit somewhere before I wrote about it, and being able to see the topography and imagine it as it was two thousand years ago was invaluable for creating the big scenes like the arrival of Boudicca's army and the fighting that followed. That said, the Colonia of Valerius's time would not have been the place it is without the help of Philip Crummy's superb book City of Victory.

Research can take you to some of the world's wonderful places

I'd love to do more research on the ground, but for various reasons that's not possible. A friend of mine who's researching a new book is off on an exotic three week trip to one of the world's most fascinating places and I'm extremely jealous. Part of one of my forthcoming books takes place in Germany and it would have been great to have done something similar. Instead, I had to turn to my old friend the internet. One of my excuses for not writing books was that I would never have had the time or the money to discover the information I needed to make it work. That's all past now. Google satellite maps and Google earth allow you not just to have a bird's eye view, but to actually walk the streets. If you want to visit a forest or a valley, someone will have posted their holiday snaps on Flickr or Facebook and with luck written a blog to tell you about the biting insects and the smelly sewage plant next door. All you have to do is use your imagination to fill in the gaps.

Of course, there is no substitute for being there and experiencing it yourself, and I'd much prefer to be swanning around the Bavarian Alps for a couple of weeks than sitting in front of this computer. But there's no longer an excuse for saying 'I can't, because ...'