Travel time maps show us how easily we can reach different location points. It’s a more accurate way of understanding locations than miles radius, which assumes that everyone can travel in a straight line. They can adapt depending on the user’s preferred mode of transport, with driving time maps shaped differently to those for public transport. Check out our isochrone guide page for more detail.
Time knows that you can cover more ground at 3 am on a Monday than 5.30pm on a Friday night. It also knows that you have to find a bridge to cross a river – you can’t just go as the crow flies. This blog explains how you can create driving time maps.
Note that the words 'travel time radius' don't really make sense, infact, if it's done right there's no such thing. That's because a radius is defined as a straight line to a circumferance of a circle- make a radius map here. But we know that real people can't travel as the crow flies, which is why travel time shapes are unusual shapes. These shapes are typically called isochrones.
Identify the map’s goal
- Who is the target audience?
- Why would they use it?
- What will they gain from using this map?
By answering these questions, you’ll be able to understand how fast the map needs to be drawn, how customisable it needs to be and how important it is to have a simple user interface (UX). For example, a GIS professional wishing to identify locations in central London with poor transport connections requires a different experience to someone searching for a place to visit for a short break.
Understand the map’s time sensitivity
Alternatively, job seekers may wish to view roles with a commute of under one hour. These maps need to account for rush hour, but as the commute repeats daily, using daily averages will provide enough precision. These time maps don’t need to account for temporary road works but provide a big picture of travelling in that area.
Sometimes specifying one specific time of day doesn’t give a good picture of access across the day. For example, a supermarket retailer may need to assess which location would be best for a new store. To do this they can assess accessibility during all opening hours, using an average time of day to level out peak congestion times.
Select the mode of transport
Decide how many data points are needed