---
path: industries/transportation
title: Transportation
desc: Find the homes more than 400 m from a bus stop.
date: Oct 21, 2026
---

# Find the homes public transport doesn't reach

Transport planners measure how many homes sit beyond easy reach of a stop. This example finds every residential building in Singapore more than 400 m in a straight line from a bus stop, from OpenStreetMap.

## Singapore homes more than 400 m from a bus stop

**Data:** OpenStreetMap bus stops and residential buildings
**Method:** keep residential buildings with no bus stop within 400 m, measured on the ellipsoid

```sql
-- Residential buildings with no bus stop within 400 m
WITH stops AS (
  SELECT geom FROM osm.public_transport_point
  WHERE  osm_type = 'bus'
    AND  geom && ST_MakeEnvelope(103.58, 1.20, 104.07, 1.49, 4326)
)
SELECT b.osm_id, b.osm_subtype AS building, b.geom
FROM   osm.building_polygon AS b
WHERE  b.osm_type = 'building'
  AND  b.osm_subtype IN ('apartments', 'residential', 'house', 'semidetached_house', 'terrace', 'detached', 'dormitory')
  AND  b.geom && ST_MakeEnvelope(103.6, 1.22, 104.05, 1.47, 4326)
  AND  NOT EXISTS (
         SELECT 1 FROM stops AS s
         WHERE  s.geom && ST_Expand(b.geom, 0.005)
           AND  ST_DWithin(b.geom::geography, s.geom::geography, 400)
       );
```

```map
singapore-homes-far-from-bus-stops
```

## Run it on your data

Upload your own stops, or the stops of a planned route, as a file or spreadsheet and swap them in for the `stops` step to see which homes they leave out. Change `400` to test another distance. See [supported files](/docs/upload-anything/files).


## Frequently asked questions

**Is 400 m a walking distance?**

No\. It is straight\-line\. Walking routes need a road network and a different method\.

**Why count buildings rather than people?**

OpenStreetMap maps buildings, not residents\. The count shows where the gaps are, not how many people they affect\.


## Next step

- [Open the map in the gallery](/gallery?industry=transportation)
- [Upload your stops](/docs/upload-anything/files)
- [Learn the SQL behind it](/docs/spatial-sql-book)
- [Book a demo](/demo)