The tools and tech used to map our world are improving all the time, and we take it for granted that we can see any part of the globe in great detail through our phone or laptop screen.

As more data is collected and digitized, another opportunity opens up: being able to take a step back in time—whether one year or a hundred years—to see how a place looked in the past.

Whether you’re investigating the spread of urban sprawl, or you just want to know what your street looked like before the turn of the millennium, these are three key resources you should be using.

Google Street View

Screenshot of Google Maps map

Google has built up many years of Street View imagery.

Google via David Nield

You may be used to checking out addresses and locations via Google Street View, but did you know that you can use it to go back in time? Obviously you’re limited by the dates that Google actually has Street View imagery for, but this now goes back decades in some areas. What’s more, you can now access historical photos on both the web and Google Maps mobile apps.

To find them on Google Maps on the web, drag the peg man from the bottom right corner of the map interface to any location on the map (the roads that have Street View pictures will be highlighted in blue as you drag). When you drop the peg man, you’ll be shown the latest street-level imagery for that location.

Look in the top left-hand corner: A small clock symbol next to the date of the photography means that you can travel back in time. Click on the date to see your options, presented in the form of a timeline slider, then drag forward and backward to look at the images from the available dates in the preview window. To get a full look, click on the magnifying glass or the images themselves.

Open up Google Maps on Android or iOS and you’ll find the same functionality, letting you see how areas have developed over time. Here you need to tap and hold on a road, then tap the Dropped Pin card at the bottom to get to Street View. Once you’ve loaded it full screen, opening the card again will give you a See More Dates link if older imagery is available.

Old Maps Online

Screenshot of Old Maps Online map

Old Maps Online links to a whole host of other resources.

Old Maps Online via David Nield

There are a variety of map archive portals on the web, but Old Maps Online is one of the most comprehensive, and a good starting point no matter where or when you’re looking. To get started, click Find a Place, or choose Browse the Old Maps if you want to see what’s available for your location.

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