The Haarlem Road Plotters

Over the last few years I've spent a lot of time curating building age maps from around the world. These are interactive maps which color individual buildings in a town or city by year of construction. A building age map can be a very effective way to visualize how a city has developed over time.

Another way to visualize the development of a city is to create a street age map.Streets in Haarlem is an interesting map which shows the age of construction of all the streets in the Dutch city of Haarlem. On this map colored circles are used to indicate the year of each road's inception.As you might guess the map seems to show that the city's oldest streets are in the center and that the streets tend to become more recently constructed as you move from the center to the outer suburbs.

You can also click on individual streets on the map to learn about the meaning behind the street's name (for example, who it was named for). The map uses information about street names and construction dates from Wikidata. 

An example of a Wikidata entry for a street in Haarlem is Mollerusweg (Mollerus Road), a road named after Johan Cornelis Mollerus and constructed in 1978. The Streets in Haarlem map includes a drop-down menu which allows you to view maps for many other Dutch towns. Unfortunately Wikidata doesn't have data on the construction dates of streets in many Dutch towns so most of these maps don't visualize the construction dates of the city's streets.However these maps do include the 'named after' data. So these maps can still be used to discover who individual streets were named for. 

If you have an interest in who streets are named after - particularly in the disparity in the number streets named for men and women in cities around the world - then you should browse through the toponym tagged posts on Maps Mania.