Why Use Isochrone Maps?

What is an isochrone map?

An isochrone map is a visual representation of which areas you can reach within a given time or distance. You might think an isochrone map looks roughly like a sphere with the starting location in the center, but this isn’t necessarily the case. Variables like speed limits, traffic conditions, and the winding of roads can create isochrone maps of all shapes.

Isochrone maps consider these variables when generating the region a person can reach within a certain travel time. Using travel time as a proxy for distance, isochrones generate maps of temporal proximity, which are much more precise than simple distance-radius maps.

Why use an isochrone map?

In most locations, all directions cannot be traversed equally. Two endpoints may be five miles from a starting location, but one could take much longer to travel to. This is due to factors outside of simple distance, including geography, traffic, and routes available to specific modes of transport (e.g. train lines, bike paths, ski slopes).

Isochrone maps calculate these factors to identify what areas can be reached within a certain time limit, allowing businesses or individuals to accurately account for commutes, delivery times, or other essential travel metrics.

Isochrone Maps in Action

Let’s consider an example. Say a business is considering where to open a factory in Seattle. They know they want the factory on the outskirts of the city, but they want to make sure it is not too far away from their employees who live downtown. 

While a commute may be only fifteen minutes for an employee ten miles away in the suburbs, an employee traveling through urban Seattle might need thirty minutes to cover the same distance. Ten miles of urban travel can take much longer than suburban travel due to higher concentrations of vehicles, stoplights, and potential slowdowns.

Using an isochrone map, a business can judge how long the commute will be for employees in different locations across the entire municipality, accounting for city congestion, busy bridges, and geographic features like Seattle’s many water features.

How do people use isochrone maps?

The practical applications of isochrone maps are multitude. This includes optimizing site selection, comparing journeys by transport mode, delineating zones for time-sensitive services, and more. Here’s how users can use isochrone maps to accomplish these solutions…

Site Selection

Isochrones provide crucial considerations for site selection. Like in the Seattle example above, a business needs to take many factors into account when deciding where to place brick-and-mortar locations to optimize accessibility.

Isochrone maps allow businesses to cross reference traffic information, population data, and distance to inform their decisions, leading them to select sites with the most efficient locales.

Journey Times for Different Transport Modes

Isochrones are also extremely useful for comparing travel times across different modes of transportation. The time it takes to arrive at a location may vary widely depending on if an individual is driving or taking public transport. 

Isochrone maps take modes of transportation into account, referencing bike routes, public transport services, and road conditions to make sure businesses understand travel time, whether they are interested in walking, biking, or driving between destinations.

Service Coverage

Considering travel time is essential for service coverage. Public service agencies like fire departments, police forces, or health care providers need to understand how accessible their sites are to the surrounding areas (and vice versa). If a government official is planning where to place the next library, hospital, or town hall building they need to accurately understand how much of the surrounding area that branch will cover.

It goes without saying that isochrones are essential for rapid response officers like firefighters and paramedics. Isochrones allow emergency responders to understand exactly how long it will take to service a critical, time-sensitive need.

Assessing Transport Networks

Perhaps a company, business, or organization is looking to improve its transport connectivity in a given region. Isochrones can help them visualize the connectivity of different parts of the area by various modes of transport.

Identifying which areas fall outside of a convenient time frame can help organizations decide how to implement the most useful modes of travel to increase connectivity. Isochrone maps can also help government officials understand which areas are relatively inaccessible so they can improve roads, traffic signage, and public transport options accordingly.

Business Intelligence

Understanding the geographic reach of brick-and-mortar locations is key to developing effective targeted advertising campaigns, identifying and solving supply chain planning problems, and understanding how customers interact with your product. Isochrones are a fundamental building block of a business intelligence solution.

What are the limitations of isochrone maps?

The only fundamental limitation of an isochrone map is that it deals exclusively with time, not distance. It will show users how far they can go in a given period of time, but will not account for the distance traveled to do so. Therefore, tracking mileage or gas expenditure will not be possible with an isochrone map alone.

However, this can easily be solved by pairing isochrone data with another mapping technology, like an isodistance map.

What is the Difference between Isodistance Maps and Isochrone Maps?

Isodistance maps show the areas on a map that can be reached at a certain distance, not accounting for time. If, for example, you’d like to find a one-mile run starting from a given location, an isodistance map will generate all the one-mile routes available from that site. This technology can pair with isochrone maps to address the limitations of isochrone data.

Create isochrone maps with Mapbox

Mapbox uses the latest in isochrone technology to provide the most accurate temporal proximity maps available. Try the Isochrone API or use Mapbox’s tutorial to see how Mapbox technology simplifies visualizing what areas are reachable in a given time limit.

The Mapbox Isochrone API calculates areas that can be reached within a specified amount of time, and displays the available regions as contours of polygons or lines on a map. This API also supports contours based on distance, so you can support your isochrone data with isodistance information.

Whether it’s logistics, navigation, or another map-driven endeavor, Mapbox Isochrones allow you to accurately compute travel time between locations, driving efficiency and creating success for your business.