A ninth century bridge over the Shannon near the monastery of Clonmacnoise has caught the attention of an archaeology professor. He believes something special, ahead of its Dark Ages time, may have been constructed in CLONMAC'S BRIDGE. Griffin Clonmac has invested five years of research in this project and now has the location for a dig. At first I thought he was based in Ireland, but then he started worrying about the cost of travelling to Ireland; I thought he must be in America. Later he wonders if he should ask the BBC for funds; so he might be in Britain. Eventually Clonmac identifies himself as being from the University of Virginia.

Another professor, Daley Garvin, is an Irishman and colleague of Clonmac's but they are not friendly. Garvin has arranged for help towards the dig, as neither man could do it alone, but the priestly authorities disapprove. The Clonmacnoise monastery, founded in 545 AD, was raided by various parties over the centuries and is a major heritage site today. A younger man, Conor MacKenna, is looking for a research project and this dig in the Shannon will do. Unfortunately during a trial dive, Clonmac is knocked unconscious - saved by fishermen - and Conor vanishes in the muddy water. Does someone intend to hinder the discovery?

Mari Quispe is a practical archaeologist who is half Peruvian, educated in England. She needs a new dig, and she's got a backlog of trouble from her last dig. Clonmac gives her that chance and together the two dive, to find carved wood perhaps 1200 years old, sitting underwater without decaying... impossible?

I felt that the story takes a long time to get moving with permits, officials, funds and unexplained hindrances. We follow a trail around many universities and archives, rather than excavating; the action is continually stuck in arguments and personality clashes. We go back in time to see the architect, a monk called Riordan, reading folios on Spanish and Roman bridges and getting building started, which I enjoyed. I wanted to like CLONMAC'S BRIDGE more than I did like it, but the concept is good and characters interesting - I would prefer if it was more tightly edited. CLONMAC'S BRIDGE gives a fascinating look at medieval Ireland and the author Jeffrey Perren has highlighted some of the headaches and dangers associated with archaeology, with a gradually strengthening romance.