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Contributing Advent 2: Opal Mews

Although OpenStreetMap in the United Kingdom, and specially in London, has come along very far, it is going to be nearly impossible to keep things up-to-date. We use a few external datasets to compare against to check for completion, and one of those is OS Locator. The fine folk at ITO World have created a comparison algorithm between OpenStreetMap and OS Locator, which they expose through a summary per area and a tile-layer as a visual aid.

I usually have to travel quite a bit from home to actually see a discrepancy, but since the update to the latest data set I actually found one very close to home: Opal Mews. On the site the discrepancy looked like:

In this case, the tag is simply missing on the way. However instead of adding the data directly from OS Locator, a survey is required. In some cases, the data in OS Locator is actually wrong, even though it's supposed to be an official source. So I went past the road, checked whether the name "Opal Mews" was visible, and added the name to OpenStreetMap:

Now ITO World's OSM analysis does not have it listed as an inconsistency anymore:

One down, 18 thousand to go!


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Great post! Just spotted one near my house will check it out tonight.

I think your changeset link is wrong. You added the street name in Changeset #19136631, not in #19099382.

@Edward: Thanks! I've fixed it.

Yes, it's very useful. I remember surveying one area of London because the OS Locator highlighted lots of discrepancies. It turned out that OS was wrong about most of them!

It was an area with a completely unpredictable pattern of apostrophes: "St Theobalds" vs "St Theobald's" etc. Sometimes the ground survey found an apostrophe where OS had none; sometimes the reverse. In those cases, I think you can also use the "not:name" tag to indicate that it definitely isn't what OS might think...

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