How far can you drive in one hour in different European capitals? This map attempts to answer that question.
The starting point for each isochrone is in the center of the city (the small white dot). For each hour of the day (0-23), a set of six isochrones with ten minute intervals (10-60 minutes) have been calculated. This is done to get a realistic view of the traffic, as the HERE.com API can take congestion in to account in the isochrone calculations. After all, the area that can be covered in the night is very different to the one during afternoon rush hour. All of the calculations result to a total of 144 isochrones for each city. These are overlaid on top of each other on the final map.
For each capital, there is a 50 kilometer buffer from the center to make the comparison easier. The maps are in Lambert azimuthal equal-area projection (EPSG:3035) so that the areas are comparable.
Data
Tools
Python, QGIS
Tutorial
I used this great tutorial from Digital Geography to get the isochrones. The tutorial also has a link to the Python scripts which can be run inside the QGIS Python Console.