FAQ


What is it?

This site was originally set up in order to compile a public domain database of postcode locations whilst people look at our old maps. Nowadays, there is a better, more complete set of data in the form of OS OpenData so there is less need of separate collection efforts. As a result, the postcode collection parts of this site have now been disabled, but you can still use it to browse some lovely old maps of the British Isles.

Some of the later parts of this FAQ still refers to the data sets which can be still be downloaded if not updated.

What licence does the data have?

The data will be will be in the public domain; consequently, users submitting data agreed to their submission being in the public domain when they entered their postcode.

What maps are you using?

We have scans of out of copyright OS maps of England, Scotland and Wales. You can register interest in future projects involving Northern Ireland.

So can I do what I like with your scans/tiles?

No. The scans and tiles have been placed under a licence; they are not in the public domain.

Okay; I can use the tiles for some things; can I download the complete set?

We have all the tiles available in a couple of different naming schemes, but not all of them are on machines with suitable internet connections for downloading from.

If you drop us an email letting us know which areas you are interested in (ideally either sheet numbers, or the whole lot), and confirm that your use falls within the tile licence, we can work out the best way to let you get the tiles. It may even be possible for us to post you a dvd of the tiles, but we'll normally request a donation to OpenStreetMap in-leui of the postage.

One thing we do ask is that if you want to use the tiles; please don't try and crawl our tileserver to obtain the entire set. Let us know what you're after, and we can probably sort something out!

It'd be really great if I could get a world file / .jpw / etc for the tiles I'm looking at, so I can feed it to gdal / mapserv / etc

It's very easy to turn a tile's URL into the location of any of its corners. We have a script that will happily spit out .jpw world files for any of our tiles, which various people make use of.

Let us know if you're interested, and we can either send you a bunch of world files, or the magic perl script.

You may also be interested in the WMS server of the tiles run by Nick Black. He gives the details of it in this blog post.

Isn't orthowotsiting an old map hard?

Luckily we're going to work in the OSGB coordinate system that matches up with the grid lines on the map; this means we don't have to distort the maps too much. We also are not overly fussy about the accuracy, so this step can be done quickly.

Why don't you use maps created from OpenStreetMap or OS OpenData data?

Because they are licensed under Creative Commons Share-alike licences, so we wouldn't be able to make the postcode data public domain.

There are people who believe that locating a point on a map creates a derived work, and hence requires a licence. We don't want to be the first to prove them wrong in a court, as that will be pricy.

If you are using scans of old maps, how accurate will the locations be?

Some of the scans are out by a degree or two but they are fairly good. We hope to be able to get better than 100 metres accuracy out of it in the end. This is more than good enough to locate a region as large as the first half of a postcode, and hopefully as much as the 'partial' postcodes described in the answer to 'What is it?' above.

How do I view maps from different decades?

For many areas, we have maps from a number of different years. By default, we always show you the most recent map we have. That gives you the best chance to locate postcodes, and allows us to produce the best list of free postcodes that we can.

However, we do understand that sometimes people would like to be able to compare how things have changed. For that reason, we provide a second interface to view our maps. With this one, we allow you to browse all of our maps from each decade.

You can browse by decade by going here. (We currently have maps from the 1920s, 1930s, 1940s and 1950s). Please note that we do not have maps for all areas for all decades, so you may find that you can only view a given place at only one or two dates.

If you have maps for an area for a decade that we currently don't, please do contact us.

I can't seem to find a certain island on your overview map

We've put together a list of hard to find islands, so you might well be able to find it from there.

Is the code behind the site available?

Yes, the code that powers the site is available in a public svn repository. You're welcome to check out the code from https://urchin.earth.li/svn/npemap/

The code is all under an open, MIT like license, see here for details.

Here's another source of free postcodes

NEW: Don't worry, so do we. The OS has released some data for free - though it's not public domain, it should be free enough for most people's uses.

There are many unattributed postcodes sets on the web, but none others (apart from freethepostcode.org, which we are already working with) which are unambiguously free. In particular there is a site which lots of people have pointed at. Unfortunately there is no actual data there; the data was removed after the Post Office issued a take-down notice to this site. We're only interested in public domain database (or possibly databases with other unambiguously "free" licensing terms).

The map doesn't join up.

Yes, it isn't perfect. The OS didn't publish a single map of the whole country, so you have to scan then stick together data from several maps. We don't really know how to correct it perfectly. It would be really cool if someone could write software to detect the gridlines and automatically cut the images up on the lines and make them square.

The wonkiness is so annoying it drives me mad, and I have experience of orthrectifying maps. Please let me straighten your maps.

Cool. Contact us, that would be great.

Why didn't you use proj/gdal?

Because we don't know how to work them. If you feel like improving how this works, let us know. Update: We do use proj for the postcode display.

Why did it take you so long to have coverage of Scotland?

While the Ordnance Survey did create the New Popular Edition maps of Scotland at 1 inch to the mile, these were never published, so we can't buy them to scan in. Scotland was included in the Ordnance Survey 7th Edition at 1 inch to the mile, but almost all of these maps remain in copyright for another few years, so we can't put them online yet

The Ordnance Survey did release some updates to the Popular Edition of Scotland in the 1940s, which had the National Grid over-printed on. them. (The War Office also published similar versions). While the grid isn't parallel with the main map, it is possible to work with (just a little bit more work). It has taken us much longer to track these down than it took us to get the England and Wales New Popular Edition maps. This is why we have only recently been able to offer a high degree of coverage for Scotland.

We now think we have completed our coverage of Scotland. Most of the maps used are from the 1940s, but there are small numbers of earlier maps (mostly 1920s), and small numbers of 7th edition maps from the 1950s. To see the coverage we have, visit the large overview map.

Why don't you have mapping data of Northern Ireland?

For Northern Ireland, the situation is harder than for Scotland, because the Ordnance Survey of Northern Ireland didn't produce an equivalent to the New Popular Edition, instead it produced a number of updates without altering the name of the edition. So, many of the maps from the Popular Edition of Northern Ireland are still in Copyright, so it's hard to know if a given old map is out of copyright just from the name.

Compounding this, it is much harder to track down second hand maps of Northern Ireland, compared to the difficulty of getting English, Welsh and Scottish maps of the period. We have also yet to come across any institutional holdings of old Northern Irish maps where the holder will allow scans to be made. All we have been able to get is quarter inch to the mile maps, which don't fit into our tiling scheme, and are too small for finding postcodes on.

If you would like to be notified when we do get out of copyright 1 inch to the mile maps of Northern Ireland, please register your interest.

Who did the work?