Discussing 'nested' cities

Parent City:
Edinburgh, Scotland - CityStrides Edinburgh (City of Edinburgh Council Unitary Authority)

Nested Cities: (Community Council Areas in OSM : 29 of 46)
Balerno, Scotland - CityStrides Balerno
Craigentinny/Meadowbank, Scotland - CityStrides Craigentinny/Meadowbank
Craigmillar, Scotland - CityStrides Craigmillar
Currie, Scotland - CityStrides Currie
Drylaw/Telford, Scotland - CityStrides Drylaw/Telford
Gilmerton/Inch, Scotland - CityStrides Gilmerton/Inch
Gorgie/Dalry, Scotland - CityStrides Gorgie/Dalry
Granton and District, Scotland - CityStrides Granton and District
Hutchison/Chesser, Scotland - CityStrides Hutchison/Chesser
Juniper Green, Scotland - CityStrides Juniper Green
Leith Central, Scotland - CityStrides Leith Central
Leith Harbour & Newhaven, Scotland - CityStrides Leith Harbour & Newhaven
Leith Links, Scotland - CityStrides Leith Links
Liberton and District, Scotland - CityStrides Liberton and District
Longstone, Scotland - CityStrides Longstone
Muirhouse/Salvesen, Scotland - CityStrides Muirhouse/Salvesen
New Town/Broughton, Scotland - CityStrides New Town/Broughton
Northfield/Willowbrae, Scotland - CityStrides Northfield/Willowbrae
Old Town, Scotland - CityStrides Old Town
Portobello, Scotland - CityStrides Portobello
Sighthill, Broomhouse and Parkhead, Scotland - CityStrides Sighthill, Broomhouse and Parkhead
Southside, Scotland - CityStrides Southside
Stenhouse, Saughton Mains and Whitson, Scotland - CityStrides Stenhouse, Saughton Mains and Whitson
Stockbridge/Inverleith, Scotland - CityStrides Stockbridge/Inverleith
Tollcross, Scotland - CityStrides Tollcross
Trinity, Scotland - CityStrides Trinity
West End, Scotland - CityStrides West End
Wester Hailes, Scotland - CityStrides Wester Hailes
West Pilton/West Granton, Scotland - CityStrides West Pilton/West Granton

Community Council Areas missing from OSM (17 of 46):
Colinton
Corstorphine
Craigleith/Blackhall
Craiglockhart
Cramond and Barnton
Drum Brae
Fairmilehead
Firrhill
Grange/Prestonfield
Kirkliston
Marchmont & Sciennes
Merchiston
Morningside
Murrayfield
Ratho and District
Silverknowes
Queensferry and District

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While Aberdeen, Scotland doesn’t have a boundary line in CS, the following all fall within the city I believe:

Parent City:
Aberdeen, Scotland - CityStrides Aberdeen (no boundary line)

Nested cities:
Bridge of Don, Scotland - CityStrides Bridge of Don
Castlehill and Pittodrie, Scotland - CityStrides Castlehill and Pittodrie
Cove and Altens, Scotland - CityStrides Cove and Altens
Froghall, Powis and Sunnybank, Scotland - CityStrides Froghall, Powis and Sunnybank
George Street, Scotland - CityStrides George Street
Old Aberdeen, Scotland - CityStrides Old Aberdeen
Seaton, Linksfield and Pittodrie, Scotland - CityStrides Seaton, Linksfield and Pittodrie
Tillydrone, Scotland - CityStrides Tillydrone
Torry, Scotland - CityStrides Torry

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Thanks, I fixed that border.

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Thanks, that now shows that the 9 nested cities only cover about a third of the parent city. Similar to Edinburgh.

This is awesome! Thanks for doing this. I’m curious if there’s a way now to create new nested cities so that gigantic areas (like Queens or Brooklyn) can be broken up into more bite sized chunks.

It depends on what data is present in OSM. For example, there’s Manhattan Manhattan, New York - CityStrides (admin level 7) and then there’s also its Community Boards e.g. Manhattan Community Board 1, New York - CityStrides (admin level 8).
Queens exists at admin level 7 Relation: ‪Queens‬ (‪9691819‬) | OpenStreetMap but I haven’t been able to find any admin levels below that within Queens…

Wish this could be done for Boston too. I would have been much more interested in trying to finish Allston or Jamaica Plain if that were the case.

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First you’d have to figure out where those boundaries even are! On the impossibility of mapping Boston neighborhood lines | Universal Hub

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A post was split to a new topic: How to add admin level data to OSM?

So what do you see this as the scope of this? Limited to fixing double street counts, or can it be expanded to split big cities into smaller chunks or combine small villages into bigger targets?

All of the city border data comes from OpenStreetMap. If sub-sections of a city exist in there, I can import those into CityStrides as nested cities.
I’ve done that for a number of larger cities & I’m happy to add more.

One thing I’ve noticed is some roads in “nested cities” that are in the nested city but not the larger city don’t count at all. I don’t know why, I haven’t investigated in OSM, but for instance in my recent activity (CityStrides) there are 15 unique street names in my completed list, but it only says 9 completed (the 9 that would previously have double-counted). Before Benfica was nested in Lisboa, this run would have shown 24 completed streets (9 x 2 + 6) but the solution to that problem now under-counts the streets I did complete :confounded:

I’ve been trying to figure out Aberdeen, actually. The smaller nested cities has been helpful to me since I live in the midst of all those, but it’s clearly a broken system. I covered a road last week (Prospect Terrace) which has the same name as a road in Dyce. OSM/CS seems to treat them as the same road, given that Dyce is part of Aberdeen (despite being significantly far apart). I wonder if mapping Dyce as a separate, nested boundary would help sort problems like that out?

I also couldn’t figure out why “Castlehill and Pittodrie” or “Froghall, Powis and Sunnybank” are a separate area of the city while Cults, Dyce, Bieldside, Kincorth, etc. aren’t. To my knowledge, these aren’t historically separate towns which merged (unlike Torry, Old Aberdeen, and Bridge of Don, but are somewhat random groupings. They don’t seem to follow any specific metrics for being bound - any insights as to what sets them apart?

I think the boundaries for the nested ‘cities’ in OSM for Aberdeen are, like Edinburgh, for community councils, but I think it may be a work in progress and not all of the Aberdeen community council areas have been added to OSM yet. Here’s the full list: Community Councils | Aberdeen City Council

Hope that helps.

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Yeah. From the perspective of Aberdeen, Prospect Terrace exists twice: Prospect Terrace - CityStrides
OSM does not have knowledge of “streets”, it only knows about ways. A Way is a collection of Nodes, and a single Way may be the entirety of a Street or it may be a section of it. Each Way doesn’t know about another Way, so within OSM there’s no possibility (that I’m aware of yet) to join up multiple Way records to determine its full street.
So, when I’m importing streets from OSM I have to figure out how to join up all these individual way records into what we all collectively know as the Street. I decided to do that based on the street name.

I expect that you completed the street within the nested city (which now doesn’t count towards your total count), but that the street in the parent city is either much larger (new city imports now cut off nodes at that city’s border) and/or the same issue :point_up: and it’s actually multiple streets.

Take Rua E for example.
You completed it within Benfica: CityStrides
But in Lisboa, there a four Rua E to complete: Rua E - CityStrides


:thinking:
I’m going to think over the idea of switching my calculations in reverse.
Instead of not counting streets in the nested city … maybe I should not count the streets in the parent city.
My immediate concern there, however, is that there are many cases of the nested city not existing (in OSM or in CityStrides).

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That would work IF the parent city was 100% covered by nested cities. Otherwise you’ll end up with streets that aren’t counted at all.

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Even if a city is “fully nested”, counting streets in the nested cities would lead to double counting since it’s common for streets to mark the border between districts/suburbs. In my view having the occasional undercount because of repeated street names (possibly solvable) is the lesser evil compared to guaranteed overcounting due to summing-up at nested level.

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Hi and thanks for CityStrides! I’m new and was recently thinking wouldn’t it be cool to see all the streets I have been running and I found this. Fantastic!

My home city Stockholm (Stockholms kommun, Stockholms län - CityStrides) has 4185 streets and it would be really nice if nested cities could be added for the 13 or 14* city districts Stockholm is divided into.

On OSM Stockholm municipality is admin level 7: Relation: ‪Stockholms kommun‬ (‪398021‬) | OpenStreetMap

My suggestion is to add nested cities for these city districts of Stockholm that are on admin level 9 in OSM
Relation: ‪Bromma stadsdelsområde‬ (‪5689303‬) | OpenStreetMap Bromma
Relation: ‪Enskede-Årsta-Vantörs stadsdelsområde‬ (‪5695996‬) | OpenStreetMap Enskede-Årsta-Vantör
Relation: ‪Farsta stadsdelsområde‬ (‪5701014‬) | OpenStreetMap Farsta
Relation: ‪Hägersten-Älvsjö stadsdelsområde‬ (‪5691404‬) | OpenStreetMap Hägersten-Liljeholmen
Relation: ‪Hässelby-Vällingby stadsdelsområde‬ (‪5690815‬) | OpenStreetMap Hässelby-Vällingby
Relation: ‪Kungsholmens stadsdelsområde‬ (‪5689375‬) | OpenStreetMap Kungsholmen
Relation: ‪Norrmalms stadsdelsområde‬ (‪5695412‬) | OpenStreetMap Norrmalm
Relation: ‪Rinkeby-Kista stadsdelsområde‬ (‪5730716‬) | OpenStreetMap Rinkeby-Kista
Relation: ‪Skarpnäcks stadsdelsområde‬ (‪5695432‬) | OpenStreetMap Skarpnäck
Relation: ‪Skärholmens stadsdelsområde‬ (‪5695372‬) | OpenStreetMap Skärholmen
Relation: ‪Spånga-Tensta stadsdelsområde‬ (‪5690852‬) | OpenStreetMap Spånga-Tensta
Relation: ‪Södermalms stadsdelsområde‬ (‪5691336‬) | OpenStreetMap Södermalm
Relation: 5691543 | OpenStreetMap Älvsjö
Relation: ‪Östermalms stadsdelsområde‬ (‪5695415‬) | OpenStreetMap Östermalm

*) To complicate things a bit just recently on 1 July “Hägersten-Liljeholmen” and “Älvsjö” were merged into “Hägersten-Älvsjö”, but that has not been updated on OSM yet. I don’t know if any regards to that should be taken.

On this I am keen to create a nested city for “Hayling Island” to the south of Havant Relation: ‪Havant‬ (‪4127867‬) | OpenStreetMap

However not sure OSM has a definition for Hayling Island from what can see on that URL?

I’m not sure if mine are being counted twice or not. They’re certainly all listed twice. For example, the walk I did yesterday says 39 streets completed. Counting the streets listed under this tab myself, there are 94. 55 of these are unique. So I’m not sure where the 39 comes from?

Also most the duplicates appear under completed once I’ve got all the nodes, but sometimes it will appear once under completed and once under progressed, though all the nodes are green. Does this mean I’m only getting credit in either Islington OR Greater London, but not both?