Follow Emperor Honorius' triumphal procession through the Roman Forum in 404 CE. Then head southeast to Tehran, and hop forward in time to June 2009 to watch the election protests unfold in Iran. How? With HyperCities.
HyperCities isn't a time machine, but it's the next best thing: a platform based on Google Maps and Earth that allows us to move virtually in time as well as space. Through HyperCities, users can combine 3D reconstructions, multimedia, archival maps, social media feeds, and hypertext to create or explore historical narratives.
The team responsible for HyperCities - a collaboration between the University of California-Los Angeles, the University of Southern California, and the City University of New York - consists of humanities scholars, librarians, programmers, and community programmers. Together they've seen the project evolve alongside web technology.
As technology evolves
In 2002 through 2003, Todd Presner of UCLA's Center for Digital Humanities collaborated with researchers at Stanford University's Humanities Laboratory to create a Flash-based mapping textbook called Hypermedia Berlin. It used manually geo-referenced historical maps of Berlin to create a web-based environment students could use to explore Berlin's history.
When Google released the Application Programming Interface for their Maps program in 2005, the creators of Hypermedia Berlin received funding to significantly expand the project, creating a participatory platform to which anyone can contribute content.
Presner described today's platform as "a generalizable, easily scalable data model for linking together and publishing geo-temporal content using a unified front-end delivery system and a distributed back-end architecture."
Because HyperCities has embraced open standards such as the geo-markup language KML, collaborators can easily add existing archives and feeds of photographs, video, audio, 3D buildings, and other content; Presner described it as "the connective tissue for a multiplicity of digital mapping projects and archival resources that users curate, present, and publish."
When you launch HyperCities, you may notice that certain cities seem to be highlighted, although the entire globe is present.
"Cities get added mainly through proposed collaborations," Presner said. "Behind almost every city is a group of content developers, who have their own teams and expertise."
Those groups of content developers have many possible motives: education, awareness, commemoration, community advocacy, or even academic research.
Exploring ancient Rome
One project, entitled "Visualizing Statues in the Late Antique Roman Forum," uses scholarly writing (complete with footnotes and historical quotations) in combination with three dimensional reconstructions of historical statues and buildings, to retrace the route of Emperor Honorius' triumphal march into Rome. The researchers who assembled the collection use it to illustrate the extent to which statues were used to further the political agenda of Honorius' general, Stilicho, who was also his father-in-law. In a more general sense, their point was to highlight the relationship between statues in the Roman Forum and the ritual processions staged there by non-resident emperors.
To those unfamiliar with that period in Roman history, the significance assigned to these statues may seem absurd. Yet, by guiding the viewer through a three-dimensional landscape to which viewers can return for further exploration, the authors succeed at effectively supporting their hypothesis.
Diane Favro, a researcher in the Department of Architecture and Urban Design at UCLA, and some of her other colleagues at UCLA, began work on the first iteration of the virtual Roman Forum in 1997. At the time, the sorts of interactive simulations they sought to create required the use of high-performance computing systems, which imposed certain limitations.
"The large size of the first UCLA models required a complex operating system and expansive computing power with trained navigators for viewing," Favro wrote in one of the papers that appears on the 'Visualizing Statues' project website. As a consequence, showings were held in the UCLA Visualization Portal, and viewers were unable to direct the motion or exploration. There was also a great deal of tension between the goals of creating a beautiful visualization that inspired a "Wow!" reaction in the audience, and creating an accurate representation that struck a good balance between giving viewers a sense of how things were while not implying knowledge of unknown details, such as the appearance of a statue that was lost.
The next iteration of the virtual Roman Forum launched online in 2003. This version included an interactive time map, textual data on all of the buildings, classical texts related to the site, and images and short video clips of the models. Although this was more interactive than the previous version, technological limitations and Internet bandwidth meant that viewers could only interact with the building models in very limited fashion. That is, viewers were able to rotate some of the buildings to see them from multiple angles; this feature showed buildings floating in a void, rather than in the context of their urban environment.
Today, the project has found a home on HyperCities. Models can be created and added using Google Sketchup, a free 3D modeling program, and researchers can build upon the models, maps, and other information others have already inserted.
The future for history
For HyperCities, the story is just getting started. More cities arranged through formal partnerships are in the works. At the same time, individuals are adding their own content to record their lives, track family genealogy, or provide information about the buildings, places, times, and people they find most interesting.
Meanwhile, development on the platform continues. When the Egyptian Revolution erupted on 25 January 2011, Presner and his colleagues Yoh Kawano and David Shepard collaborated to create something they called HyperCities Now. They managed to launch the new version of their platform in only three days, allowing them to provide the world with a timely, highly relevant visualization of social media connected to the ongoing protests in Egypt. Today viewers can navigate back in time to the day the protests started, and watch the tweets as they unfold, overlaying a satellite map of the region.
The ability to place tweets according to their time and place is a useful feature; it will even automatically populate the maps with a plethora of content on recent history. But at present, it isn't integrated into the rest of HyperCities.
"I would like to integrate the social media feeds (HyperCities Now) with long term historical content of cities," Presner said. "I think the project offers some interesting explorations of an expanded and participatory public sphere."