A map doing the rounds at the moment (thanks to a plug from flowingdata) is Derek Watkin’s brilliant map of “generic” terms for rivers in the United States (below).The map shows how different cultural and linguistic factors have influenced the naming of geographic features in the US. For example French settlers named the streams they encountered “bayous”.
The number of rivers in the US, combined with Derek’s brilliant design, make this a really compelling map. Inspired by this work I have quickly (with much less cartographic flair) extracted the major rivers and streams in Great Britain from the Ordnance Survey’s Strategi dataset and coloured them according to whether they are a “river”, “canal” (not sure if this really counts in terms of naming), “water”, “afon” (Welsh for river) and “brook”. You can see that a clear geography exists. I was not surprised by all the “afons” being in Wales but I was surprised to see so many “waters” in Scotland.
On the topic of naming, settlement names also have a clear geography as they, like rivers in the US, reflect the different settlers (or invaders!) of the British Isles over millennia. The map below (taken from my thesis) shows the different naming influences on settlements in Britain. The most striking aspect is the abrupt end to the Viking settlement names along what is called the Danelaw Line. So if you live north of this line you will be using more Viking words on a daily basis than those to the south. There are loads of people studying and recording the different place naming conventions in Britain- I would recommend you check out the “Institute for Name Studies” if you want more information.