OpenStreetMap
Not the entire city, but the place node, for Hyderabad, a city of over 7 million people… which currently has no label.
See the unlabeled city here: https://www.openstreetmap.org/#map=10/17.3382/78.5502
It seems unlikely that there never was a label, which means that somebody probably deleted it accidentally, or otherwise accidentally changed it in some way which prevents it from appearing (e.g. change “place=city” to “place=City”) It is also missing from Nominatim. Is there no bot or other process checking for when something huge like this disappears from the map?
Discussion
Comment from lxbarth on 13 June 2015 at 20:09
Nice find.
I added a rudimentary city node until the original one is recovered http://www.openstreetmap.org/changeset/31950230
Please report such issues to the data working group (data@osmfoundation.org). I just notified them of the issue.
Comment from SomeoneElse on 13 June 2015 at 21:31
Was the previous one perhaps http://www.openstreetmap.org/node/245640543/history ? It was at least a previous one, I presume. The changeset that deleted it just looked like normal mapping, so it might just have been an accidental deletion. However this was 2 years ago, so maybe there’s been a more recent one since? City nodes accidentally disappearing isn’t that unusual; it has happened to the nearest city to me (Sheffield) a couple of times recently.
It might be worth mentioning it in the “users: India” section of the OSM Forum, or perhaps the talk-in list (both relatively low volume, but active) to see if anyone knows more of the story (or I can, if you’d prefer). Thanks too to Alex for the notification.
PS: In case you’re wondering how I found that old node it was finding a local suburb node and then finding a changeset that modified lots of place names, and looking for the name “Hyderabad”.
Comment from Warin61 on 14 June 2015 at 00:30
Yes .. nice find .. I’ve an OSM velo map of India from October 2014 .. and it is missing there/then (and I did not notice!)
Comment from andygol on 15 June 2015 at 05:50
I reverted previously deleted point for Hyderabad, India (thanks Andy for extra information) - http://www.openstreetmap.org/node/245640543/history.
I deleted temporary node created by Alex.
See - http://www.openstreetmap.org/changeset/31952247
Thank you all for participation in this case
Comment from bdiscoe on 15 June 2015 at 06:16
Thanks for the great work everyone, I see Hyderabad is back on the map. I also refreshed the main site’s cache so it appears on zoom levels 7-12. It’s even showing up in Nominatim - that was fast!
I am wondering about setting up some kind of process to get notified when someone deletes or commits a change anywhere to a place=town or place=city. We could catch this sort of thing more quickly and not have to wait for someone to stumble across it.
Comment from SomeoneElse on 15 June 2015 at 11:30
Re “detecting when someone deletes a city”, it’s not quite as straightforward as just reading the minutely updates or looking at changesets within a bounding box, because the XML itself doesn’t contain details of a node being deleted - just the fact that a node was. It might be the corner of a bulldozed building, or it might be a city of 7 million people.
Querying every deleted node for every changeset (even from something like Overpass) is unlikely to be practical. More of an option might be some kind of database trigger http://www.postgresql.org/docs/9.3/static/trigger-definition.html - even a rendering database should have enough information in it to tell when a city’s been deleted.
Comment from naoliv on 16 June 2015 at 04:41
(please, don’t say that this method is stupid) :-)
What I do when something is deleted in Brazil and I need to find the node: grep Brazil’s full history dump. With some black magic it’s possible to find all the
placenodes with a specific name (or other characteristic) and see if the node IDs are still available in the OSM (or if they were deleted).For our cases, it’s quick to grep a ~4GB file and the results are very good.