OSMnx · Measure accessibility

Generate walking isochrones around a point in Burjassot, extract a single-radius neighborhood, and cluster nodes by network distance.

This walkthrough mirrors the Accessibility panel.

Before you begin

Download a walk network and project it (see Clean up the graph).

1. Set the center

In Accessibility, choose the Center Node (use the eyedropper to click a node in the viewport, e.g. the town center).

Selecting the isochrone center node.

2. Isochrones

Set:

• Trip Times: 5, 10, 15, 20 (minutes).
• Travel Speed: 4.5 km/h (walking).
• Mode: Buffer Union (smooth blobs) or Convex Hull (simpler shapes).

Press Isochrones. Nested polygons show how far you can walk in each time budget.

Nested walking isochrones around the center.

3. Ego subgraph

Press Ego Subgraph to extract the sub-network within a network-distance radius of the center node — handy for isolating a neighborhood.

The ego subgraph around the center node.

4. Network DBSCAN

Press Network DBSCAN to cluster nodes by network distance using eps_meters and min_samples. Clusters reveal pockets of dense connectivity.

Network DBSCAN clusters coloured by label.

Next steps

Continue with Compute statistics for morphometrics and street orientation.