The Built/Unbuilt Square provides a journey into Rittenhouse Square's historical landscape with the help of augmented reality technology. Passersby are invited to look into a pair of viewfinders—a traditional device often placed on the edge of important monumental vistas—with each facing inward at the park. Within the scope of each viewfinder, the park can be seen as layered with archival images of historical gatherings, renderings of constructed and proposed structures from past eras, and animations conveying the square’s vitality and mythos. Users can shift the angle of the viewfinder to reveal multiple views of the location they are currently inhabiting. Together, the viewfinders of The Built/Unbuilt Square attempt to collect the stories, fragments, and numerous evolutions of the park into a shared frame.


Location: Site 04: Rittenhouse Square
The project will be on view to the public through Sunday, November 5.

Lab Hours: Closed

Park Hours: Open 6am – 1am Daily



Saturday Spotlight
1pm – 4pm



Learn more about the Rittenhouse Square artists and their projects at a special exhibition at the Philadelphia Art Alliance.

September 13 – November 5: Tuesdays through Sundays, 12pm – 6pm Closed Mondays


Modified coin-operated binoculars, steel, cement, aluminum, iPads, optics, augmented reality software, high-capacity battery packs, black paint, wood, glass, and Rittenhouse Square

The Built/Unbuilt Square Collaborators

Night Kitchen and Hilary Wang

Site Partners

The City of Philadelphia, Philadelphia Parks & Recreation, Friends of Rittenhouse Square, and Philadelphia Art Alliance

Project Manager

Corin Wilson



Artist Statement

Rittenhouse is the only one of William Penn’s proposed squares to stay true to its original purpose, first depicted on a map by Thomas Holme in 1683, a proposed grid of the then-nonexistent city to attract English investors (all the other squares were at some point cemeteries and, in the case of northwest square, public gallows). Looking around the square today, one might wonder how this planned green space ended up containing so many disparate, and in some cases disharmonious, elements. The research attempting to answer this question revealed a great quantity of proposals built and removed, unrealized, temporary and partially completed: an unusual series of structures and events that leave the square with a confusing collection of fragments of mistakes, replacements, and long-forgotten intentions.

My proposed monument acknowledges this site’s constant flux while subtly physically altering the square. What will it look like to see every proposal that has ever been documented for the square? What is it to experience the site today, absent the effects of time?

Viewers will be able to look through and manipulate a pair of binocular viewers mounted on the northeast and southwest entrances to the square, facing inward. They will see a ghostly version of what has, could have been, and never was, all occupying the same space. Other than the viewing devices, a single physical structure will offer a hint to the vast virtual augmentation.

With the aid of augmented reality and modified coin-operated binocular viewers, visitors will be able to see many structures that have been proposed for the site but never built, structures that have been built and removed, and a series of elements that have been altered or moved, all superimposed on the site as we find it today.



The Built / Unbuilt Square: Northeast Viewfinder

The Built / Unbuilt Square: Southwest Viewfinder

The Viewfinders in Rittenhouse Square allow viewers to look into the past. While playing a video, click and drag to navigate the environment.



Lantern Room, 2016. Dimensions variable. Neon sign, hardware, transformer, microcontroller, sensors, beating heart. Courtesy of the artist.

About the Artist

Alexander Rosenberg is a Philadelphia-based artist, educator and writer. He received a BFA in glass from Rhode Island School of Design and Master of Science in Visual Studies from Massachusetts Institute of Technology. His artistic practice is rooted in the study of glass as a material, in conjunction with broad interdisciplinary investigation crossing over into many other media and research areas. 

Alexander pursues his practice with artist residencies, teaching, performances, curatorial projects, and exhibitions locally and internationally. He is the recipient of the 2012 International Glass Prize, The Esther & Harvey Graitzer Memorial Prize, UArts FADF Grant, and the deFlores Humor Fund Grant (MIT).  He has attended artist residencies at The MacDowell Colony, Urban Glass,Vermont Studio Center, StarWorks, Pilchuck Glass School, GlazenHuis in Belgium, Rochester Institute of Technology, and Worcester Craft Center.  His writing has been published in Glass Quarterly, The Glass Art Society Journal, and the Art Blog.  He is a founding member of Hyperopia Projects and heads the glass program at University of the Arts.


Banner: The Built/Unbuilt Square, Alexander Rosenberg. Modified coin-operated binoculars, steel, cement, aluminum, iPads, optics, augmented reality software, high-capacity battery packs, black paint, wood, glass, and Rittenhouse Square. Rittenhouse Square. Photo: Steve Weinik.