The most important archaeological site in London?

Heritage Key have unleashed their second Bloggers’ Challenge. This time they’d like to know what the most import­ant site in London is. Once again I’m not enter­ing because of Rule 19, but it’s still an inter­est­ing ques­tion. This time around it won’t go live till after the event. I think I’ve gone for an obvi­ous answer and I don’t want ruin it for any­one else who’s come up with the same idea. The only twist is that some of the most import­ant site in London isn’t even on the same con­tin­ent anymore.

London Bridge

London Bridge, Lake Havasu AZ. Photo (cc) Larry Page

It has to be London Bridge. All the other major sites of interest to tour­ists like the Tower of London, Buckingham Palace or the Oxford Circus branch of McDonalds, only exist because of where the bridge was built. Even some­where like Greenwich Observatory, where the world is told what the time is, ulti­mately exists where it does because of the bridge.

Finding the ori­ginal bridge over the Thames sounds quite dif­fi­cult. There’s the usual archae­olo­gical prob­lem that wood leaves little trace in the soil. Added to that are the prob­lems that the soil is under­wa­ter and, in suc­ceed­ing years, people have built massive bridges over the site. That’s an effect­ive way of oblit­er­at­ing any earlier traces. One reason for think­ing that the bridge was built at this site isn’t any remains of the bridge itself. It’s the things that people have thrown off it. Roman coins were found in the gravels under the bridge when later bridges were built. This could be wash of mater­i­als into the river from wherever they were lost, but the con­cen­tra­tion under the bridge marks this out as a spe­cial site. The ori­ginal loc­a­tion was chosen as a con­veni­ent site, but its revival was as a delib­er­ately incon­veni­ent site.

The bridge seems to have gone out of use in the 4th cen­tury AD. After this period cross­ing of the river would have been by ferry. This would not really have been odd. At this time rover trans­port was cheaper than road trans­port and so rivers would have been the high­ways of the ancient and medi­eval world. The river was nav­ig­able to sea-going ves­sels, moved by free wind­power rather than expens­ive grain-fed animal power. That makes build­ing a bridge across the river, block­ing the move­ment of ves­sels, a very con­trolling act and that’s why the bridge was rebuilt in the 990s [PDF]. Building a bridge across the Thames acted as a bar­rier to Viking incur­sions upstream.

Once it was built you not only had a bar­rier to mil­it­ary ves­sels, it also became the end of the river for large mer­chant ships. The docks down­stream of the bridge became the eco­nomic ful­crum of the city and its hin­ter­land. London con­trolled the trader for everything trav­el­ling by river from as far away as Oxford. Wherever the low­est bridge­able point on the river was, that was where the city would be.

Other sites became import­ant partly due to their loc­a­tion in London. The only excep­tion is the bridge, which set the loc­a­tion for London. When McCulloch bought London bridge for his new city at Lake Havasu, and not Tower Bridge, he was buy­ing the bridge that mattered.


When he's not tired, ill or caught in train delays, Alun Salt works part-time for the Annals of Botany weblog. His PhD was in ancient science at the University of Leicester, but he doesn't know Richard III.