“Music is liquid architecture; Architecture is frozen music.”
-Johann Wolfgang von Goethe
Dedicated December 2010, only a few years before his passing, the Soleri Bridge and Plaza is Paolo Soleri’s parting gift to our world. The bridge was designed to bring awareness of our human connection to the sun and our natural world. Designed by Soleri and constructed by the City of Scottsdale as homage to his lifelong work and commitment to organic architecture and humanity the 22,000 square-foot plaza along with a 100-foot-long bridge span a portion of the SRP canal just south of Camelback on Scottsdale road and is a main pedestrian thoroughfare in Old Town Scottsdale. The entire site is a solar marker/calendar and like all of Soleri’s work was designed to be an organic component to a sustainable urban lifestyle. Marking the summer and winter solstice as well as celebrating the spring and autumn equinoxes the site is a masterpiece of art, function, and design. The site incorporates steel pylons, a monument wall, and earth-cast concrete panels tying together this modern steel solar marker with Soleri’s earlier organic roots.
The utter brilliance of the site is that the structural support for the bridge and the solstice marker are actually one in the same. The site utilizes the bridge as an integral component while marking the winter solstice, and on the summer solstice, the pylons which support the bridge cast no shadow as the angel of the pylons are fixed to both support the weight of the bridge while simultaneously pointing directly at the noon-day sun. Philosophically this is a perfect hermetic architecture.
Process and Collaboration
Scottsdale Public Art lead the project bringing together the architect of record, structural engineer, and landscape architect as well as facilitating all aspects with the city project manager, Soleri students, the Salt River project, and Federal Bureau of Reclamation. the project took two years to design followed by eight months of construction during which the team addressed issues of bridge height, true north axis, and underground utilities that feed the downtown Scottsdale area its power. Future construction projects also had to be taken into consideration as this is a solar calendar and would cease to be functional if it were ever to be shadowed by a taller structure.
How it Works
Summer solstice. June 21st (Longest day of summer)
Brilliant in its simplicity; the four pylons that make up the support system for the bridge are set at such an angle that at noon they cast no shadow as they are pointing directly at the sun.
Winter Solstice. December 21st (Longest day of winter)
The two 64 foot pylons that dominate the site along with a shorter set of pylons to the south are in exact alignment to true north. Both sets of pylons are spaced exactly six inches apart as to form a blade of sunlight that travels north illuminating a red painted line on the ground that extends across the entire bridge. Since the sun is at it’s lowest in the sky on this day and has dropped south in it’s traverse across our sky the shadow it casts from the pylons is at it’s longest. This is visible at noon, give or take 40 minutes, on the summer solstice.
Other Solar Sites in Arizona
The Soleri bridge is far from the only solar marker in Arizona. It seems there are quite a few both ancient and modern dating back to the Hohokam. Notice that most of these are ancient and imagine for a moment how many sites have probably been lost to time.
Hole-in-the-Rock– Located in Papago Park, hole in the rock is an ancient Hohokam astronomy site. Open to the public it is a short hike up the rock to location. Hohokam Shamen noticed that the sun moved across the floor of the cavet differently at different times of the year but always repeated the same path. They pecked holes into the floor of a cavet directly underneath a hole-in-the-rock and at the same time every year the sun is shown on the markings, ergo a calendar.
Chaco Canyon– Too much to go into here. Entire books have been written about this site and the advanced
architecture and solar mapping that took place there.
This may have been one of the 7
Circlestone– Located at the top of Mount Mound in the heart of the superstitions, This is an extremely complex site
not yet fully understood. I have written an article on this site here.
Pueblo Grande– Also located in the Papago Park area this Ancient Hohokam platform mound has a room that lines up with the sun on the summer solstice. I’m sure there is more than that there but I’ve yet to dive into that research.
Casa Grande– Another Hohokam site. Casa Grande also incorporates solstice, equinox, and other astronomy architecture.
Signal Hill– Located in Saguaro National Park West and of Hohokam origin. Once thought to be just another petroglyph Tucson resident Nile Root believes he has unlocked the secret of this site. This may very well be one of the most complex solar calendars ever created by primitive man. Simply put, it is whats referred to as a Sun Dagger, but it’s much too involved to go into here and definitely deserving of its own page on this site. I’ll leave it to you to investigate if this has sparked your interest. Here is a link to Nile’s site. http://www.niler.com/s1.html
V Ranch– Located near Sedona in the Verde Valley, this is an ancient petroglyph site made by the Sinagua culture who once lived the area. The spirals on the rock face are known to align with specific days of the year, with shadows moving across the surface of the petroglyph.
Other Modern Solar Sites
Tree of Life– Located on the South West corner of 68th street and McDowell, the “Tree of Life” is a modern day recreation of a Hohokam flood water catchment. This site is the result of a national public art competition. The site is a boundary marker for the cities of Phoenix and Tempe and the pillars have quickly become an icon of the Papago area. The pillars line up with the rising of the sun at summer solstice.
Carefree Sundial– Located at 100 easy street, in the town of Carefree, AZ. It was completed in 1959 and is the largest sundial in the country. It stands 35 feet tall, extends 72 feet and is the 90 feet in diameter. Designed by solar engineer John Yellott and Architect Joe Wong it was built to attract tourists and prospective home buyers to the area.
This is by no means a complete list and I’m sure I could go on for quite a while but you get the idea.
It seems that the sun has always been celebrated across the deserts of the world, and Phoenix, AZ is no exception to this. Just like the Hohokam, we are building monuments to this ancient “giver of life” and keeping this tradition alive. An effort that seems to tie our past with our present and moves us into the future all at the same time. The Soleri bridge ties together the ancient solar observances and lives of the indigenous peoples of the desert with modern day engineering marvels of today’s desert inhabitants. It crosses a modern-day canal that symbolically joins our two cultures together as well. The city of Scottsdale uses the plaza regularly for events and the bridge is used daily as a route to conduct daily business and travel. The minds behind this structure truly built a multidimensional bridge, a concept Soleri thought and wrote about quite often. Next time you’re in Old Town Scottsdale take a few minutes at the Soleri Bridge and see if you can discover some other dimensions I may have missed.