Overview

This tool allows you to create polygons on the map representing how far you can drive, walk or cycle in set amount of time. This is a more accurate way of showing how far someone can travel compared to using concentric circles that don't take into account the road and path network.

Method

Creating an Isochrone 

1. Open theToolsmenu and clickIsochronemenu item to open the tool
2. In the left-hand panel, select theDriving, Walking or Cycling option
3. There are three default times, 5, 15 and 30 minutes. You can change these as required.
4. Click on the mapwhere you want your isochrones to be calculated from.
5. The isochrones will appear on the map.

Modifying an Isochrone

• To change the travel type, click the driving, walking or cycling buttons. This will change the results on the map.
• To change the times, change the values in the option boxes. This will change the results on the map.

Saving an Isochrone

A set of isochrones can be saved to any editable polygon layer you have in your account.

1. Click theSavebutton. A box will open asking you which layer you'd like to save them to.
2. Use the top drop-down box (Select a Layer) toselect the layer you want to save them to. Once chosen, the attribution for that layer will show, allowing you to add any other information you like.
3. Use the next drop-down box (Time Value Column) tochoose a column to add the time values into. This means that the saved polygons will have the time you set as attribution for future reference.
4. ClickSave.

If your layer has a column called "Isochrone" then the tool will automatically add a number (usually, 2, 1, 0) to to polygons as well. This will help when it comes to styling the layer.

Deleting an Isochrone

When you close the tool, any unsaved isochrones will disappear from the map.

If you've saved isochrones to a layer then you'll need to delete them using the normal method of selecting them on the map and clicking the Delete button.

FAQs

How accurate are these isochrones?

They are calculated using the latest map data from around the World, but of course in some areas there may be discrepancies or omissions.

For driving calculations it uses road speeds and for walking and cycling it takes a typical speed for those methods of transport.

How are the driving distances calculated?

The algorithm takes mapping data from OpenStreetMap to determine the road size and type, and then uses a 90 day rolling average of historic speed data to work out how far a car can travel.

How are the walking and cycling distances calculated?

The algorithm takes mapping data from OpenStreetMap to determine the walking and cycling infrastructure and applies a average speed for those two types of travel methods. This is in the region of 5 kph (3.1mph) for walking and 16 kph (9. for cycling.

When I save the isochrones to a layer they're not in the colour I want them. How do I fix this?

You can use the styling options for that layer to make the changes to styling as you require. It's advisable to have a column in the layer called "isochrone". If the software spots this column it will populate it with values to help with styling.

Does this do point-to-point routing?

No, but we hope to have this feature in the future.

Why isn't there a public transport option?

The underlying data and service we use doesn't include a public transport option so we can't calculate them in this tool.