http://www.digitaljournal.com/technology/google-street-view-lets-you-time-travel-into-the-past/article/381861

Google Street View lets you time-travel into the past

Posted Apr 23, 2014 by James Walker
As of today, Google has begun rolling out a new feature for Street View, the component of Google Earth and Google Maps that lets you view places as if you were actually there, that allows you to travel back in time and view the place in the past.
Google building sign
Google building sign
Justin Sullivan, Getty/AFP/File
Although the feature can not be used in all locations, most high-profile destinations are included. The functionality is indicated, if available, by the presence of a small clock icon in the upper-left corner. Clicking the icon opens a popup that enables you to choose a time to travel back to and see how the location looked to passers-by on that date or see how the area has changed and evolved over the years.
However, Google only thought of the idea in 2007 and have only been collecting data, in the form of snapshots from Google Street View, since then so only that period of seven years is covered. It is still a good way to see how some of the most famous urban locations on the planet have changed over the course of the past seven years and also enables us to see accurate before and after images of natural disasters such as the Japanese tsunami on 2007 despite not all cities worldwide being featured yet.
Google Maps and Google Earth have had a similar functionality for years, however, enabling users to see how the surface of the world has changed. This feature also draws on archive footage from up to 50 years ago, though, and it would be good if this new Street View functionality could also access this archive content in the future.