UPDATE 07/02/2014 : Read the associated comment on this post from Phil at the Ordnance Survey, quite possibly the best response I’ve ever had on this blog, thank you.
UPDATE 07/02/2014 2: Old Maps at end of this post courtesy of ‘Phil Allen’ FSE Manager at the Ordnance Survey, thank you!
Working with real 3D models of London it sometimes makes sense to place this in context on a boundary map, but I’ve run into to something that’s given me pause for thought….
The City of London is an odd and special part of London I think you’ll agree, I’ve always known it’s administrative boundary as being a little odd (something about bridges…) sure enough on the City of London website there is the boundary showing clearing two bridges are covered in its area.
Now being a GIS sort of fellow I want to download this boundary set, so visiting the OS OpenData site, I see that something’s up whilst one bridge is clearly there on the left, London Bridge has been excluded (hence my clever title). What does it all mean? Well I think probably OS Opendata is generalised in some way and this bit got missed… but I don’t really know. Downloading boundary data from the Greater London Authority data site doesn’t fix things either (it is just the data set the OS gives).
So what does this all mean? Well it means that the OS may well be the ‘authoritative geographic data’ set for the UK, but it doesn’t mean everything you get from it is without ‘issues’. Know your data, know its limitations, also did I mention OpenStreetMap seems to get it right? Why am I relying on data from the OS again?
UPDATE 07/02/2014 1: Read the associated comment on this post from Phil at the Ordnance Survey, quite possibly the best response I’ve ever had on this blog, thank you.
UPDATE 07/02/2014 2: Old Maps below courtesy of ‘Phil Allen’ FSE Manager at the Ordnance Survey, thank you!