While water towers or steeples defined some city skylines, large oil silos punctuated the horizon of the Kruunuvuorenranta area in Helsinki, Finland. With the city’s ongoing redevelopment of this once-thriving port into a residential district, most of the structures were removed save for one. To promote the area’s new identity as a “district of light,” Helsinki held an international design competition to transform the last remaining waterfront silo into a permanent art installation and public space.

The winner of the competition was Lighting Design Collective (LDC), a Madrid-based practice founded by Finland native Tapio Rosenius. LDC proposed drilling thousands of holes into the silo drum and illuminating some of them with blinking LEDs. The 17-meter-tall (55.75-feet-tall) drum with a 36-meter (118-foot) diameter sits on the ground along the water. “Entering the silo is almost like walking into the Pantheon,” Rosenius says. “Its perfectly round steel drum has a templelike quality.”

Though the sturdy structure did not need reinforcement, it did require a few updates, including a new concrete floor, and water and power connections. Sandblasting the existing paint, which didn’t meet environmental standards, ate up most of the allotted renovation time. The exterior was repainted white and the interior a deep red color similar to the silo’s rust.

Those original rust patterns that covered the silo’s interior inspired LDC’s artistic interventions. The team photographed the patterns and created half-tone images; the pixels were then translated and integrated into the pattern of holes around the silo’s surface—2,012 holes total, to be exact, in recognition of Helsinki’s tenure as World Design Capital of the year.

One worker with a flame-cutter made each of the 150-millimeter- (5.9-inch-) diameter holes—a challenge given that the silo’s shell is 22 millimeters (nearly 1 inch) thick at its base. The holes allow for smoke extraction, air circulation, and daylight penetration. They also fulfill an aesthetic need. Throughout the day, the silo appears to shimmer, thanks to 400 polished stainless steel discs measuring 50 millimeters (nearly 2 inches) in diameter. Spaced at random intervals around the drum, the mirrors sit flush against some openings and flicker in the wind. At night, 1,280 warm-white LED dome luminaires in the evenly spaced holes set the silo aglow. Steel brackets attach the mirrors and LEDs to tensioned steel wires that run vertically inside the silo wall.

In developing the pattern for the lighting, LDC analyzed the area’s prevailing winds and the swarming patterns of birds. Following nature’s cue, the designers avoided creating a repetitive light show, which would become tedious for residents. “In nature,” Rosenius says, “there are opportunities to look at movement without ever getting bored with it. Watching a river flowing or seawater rippling remains fascinating and beautiful even when you stare for hours.”

LDC created custom software to control the LEDs. Within the video game industry, some coders develop algorithms that mimic nature and then make their code available as shareware. LDC’s designers downloaded and tweaked OpenFrameworks, an open-source C++ toolkit, to include parameters such as wind speed, direction, and temperature. Housed inside the silo, the computer system, an industrial model from Siemens used to control factory robots, dials out every five minutes to download local weather reports via a 3G modem. The data directs the movement of each particle of light, which is imbued with a similar level of artificial intelligence, much like a bird within a flock. The pattern of the lights is unpredictable even for the designers.

Since the silo predominately serves as a space for contemplation, the designers kept its interior free of clutter, save for a simple concrete bench that rings the perimeter. LDC added rigging under the roof to increase the space’s versatility. Silo 468 has been a set for TV programs and commercials, as well as a stage for poetry readings and fire-juggling shows. Potential future uses include a wedding venue and ice rink. Perhaps the only disappointment of the space is its acoustics: The silo is not conducive for hosting rock concerts. A shame, Rosenius says half-jokingly, given Finland’s affinity for heavy metal.