Philadelphia is home to over 500 bridges, connecting people across the city. But one bridge stands out from the rest—it’s made entirely of glass.
This 30-foot-long structure, called “Glass Bridge: The Penn Monument for Hope,” was designed by architect and structural engineer Masoud Akbarzadeh and his team at the University of Pennsylvania.
Unlike traditional bridges that use steel and concrete for strength, this bridge is built from interlocking hollow glass units.
At first glance, it looks delicate, almost like a floating sculpture. But thanks to smart engineering, the bridge is incredibly strong.
Glass is usually seen as fragile, but Akbarzadeh and his team found a way to make it work by designing the bridge to handle force through compression.
Each glass unit supports the others, allowing the entire structure to distribute weight efficiently. “All these pieces alone might seem brittle, but together, they gain strength,” says Akbarzadeh.
This idea isn’t new—it goes back thousands of years. The Romans and Mesopotamians built arches that used compression to support massive structures. In the 17th century, scientist Robert Hooke discovered that an inverted hanging chain forms the perfect shape for an arch, leading to stronger and more stable structures.
Akbarzadeh applied these ancient ideas to modern materials, using cutting-edge computer design and engineering.
Years of planning, weeks of building
The idea for the Glass Bridge started in 2017, and it took six years of research, design, and negotiations to bring it to life.
Before constructing the full-scale bridge, the team built a 10-foot prototype to test their ideas.
They experimented with different types of connectors and materials to find the best way to assemble the glass without causing cracks or weaknesses.
Eventually, they found success using precision-cut acrylic connectors and a special industrial adhesive. The final bridge consists of 124 separate glass units, all cut to exact measurements with less than 0.1 millimeters of error. Even the slightest misalignment could have caused the entire bridge to fail.
A race against time
Although the team had carefully planned every step, challenges arose. The glass units had to be shipped from different countries, but delays pushed back their arrival, leaving the team with just 21 days to assemble the bridge before its scheduled unveiling at the Corning Museum of Glass in New York.
For three intense weeks in November 2024, engineers, architects, and researchers worked long hours lifting heavy glass pieces by hand, checking measurements, and carefully fitting everything together. Because glass is fragile, there was no room for mistakes. “We had to physically lift and position each unit by hand,” says Boyu Xiao, a research assistant who played a key role in the construction.
One of the biggest challenges was ensuring that the bridge could stand on its own. Like any arch, it needed a keystone—the final piece that locks everything together. Until that last unit was in place, the entire structure was unstable. After days of problem-solving and late nights, the team finally installed the last piece on November 30th. The bridge was complete.
A symbol of strength and innovation
Now on display at the Corning Museum of Glass until September 1, the Glass Bridge is more than just an engineering achievement. It symbolizes human connection, trust, and collaboration. Akbarzadeh compares the bridge’s design to society, saying, “For a better-functioning world, we need to rely on each other. Only with transparency and teamwork can we create something great.”
Despite all the challenges—years of planning, stressful shipping delays, and the pressure of working with fragile materials—the team succeeded. As Xiao puts it, “Against all odds, we actually did it.”
Source: University of Pennsylvania.
