I built it to quickly compare and contrast Australian cities with their international counterparts. Clicking on any statistic opens an Overpass Turbo query displaying the relevant data.

I previously wrote a blog post on turn-by-turn bicycle navigation apps that use this data at The Best Apps for Bicycle Directions (2020).

Architecture

The website is a simple frontend React Typescript app, however the data is statically compiled into a large JSON blob.

Generating the JSON blob requires thousands of Overpass Turbo requests. These requests are cached at build time on the filesystem using a hash of the query string as a key. This currently requires clearing the cache to completely regenerate data to fetch new updates from OpenStreetMap. When generating data for Australian councils I use a self-hosted Overpass server (also improving speed dramatically), while using overpass-api.de for the few international examples.

I could achieve a faster first paint by async loading this JSON blob at runtime but I haven’t yet implemented this.

Population counts are sourced from Wikidata (and pregenerated in the JSON blob) based on the wikidata tag on OpenStreetMap relations.

When area names have a non-english name (identified by a name:en tag present), both English and local names are displayed.

Overpass queries

Overpass queries are written in https://github.com/jakecoppinger/australian-cycleway-stats/blob/main/static-backend/src/utils/overpass-queries.ts and are somewhat complex. They contain some “opinionated” tradeoffs (informed by policy) in what roads are considered safe (<= 30kmh) and what is considered a dedicated and shared cycle path. Improvements or questions are welcome!

The post Which Australian councils are building the most cycleways? first appeared on Jake Coppinger.