With its undulating roof profile, the Coliseums, a complex built for the 2010 South American Games in Medellín, Colombia, appears as a mountain — albeit a caricature of one — in the midst of the city. Indeed, the design team, the offices of Bogotá-based Mazzanti Arquitectos and Medellín-based plan:b arquitectos, conceived the project, which is sited in surreal juxtaposition to the Andes in the background, as a new landform within the Aburrá Valley.

Shortly after Medellín was selected to host the 2010 South American Games, the city (which has been much hyped for its recent architectural renaissance) set forth plans for significant investments in athletic facilities. And, in mid-2008, in cooperation with the public agency Institute for Sports and Recreation (INDER) and the Colombian Society of Architects, it sponsored an open international competition for a series of gymnasiums. The selected site housed preexisting sporting facilities, such as a stadium and aquatics center, some of which had fallen into disrepair. Among these was the Iván de Bedout basketball coliseum built for the 1978 Central American Games. The competition brief called for a new facade for this arena, as well as three new facilities to accommodate gymnastics, martial arts, and volleyball. With the March 2010 Games creating a hard deadline, the winning team had just 18 months from competition to completion of the 493,000-square-foot, $50 million project.

“We conceived of the four buildings as a single large urban structure with sporting arenas and covered areas for public zones,” says plan:b’s Felipe Mesa. “Basically, what we did was to make these four buildings with the same modules,” notes Giancarlo Mazzanti. “Every piece of one building is identical to the pieces of the building next to it, just arranged differently.” To start, the team removed the roof of the existing gymnasium, retained the concrete risers, and reinforced the structure for seismic resistance. They then designed six different trusses and ordered them in unique parallel configurations for the existing arena as well as each of the three new buildings. This system of modular bands enabled the manipulation of the section to accommodate the vertical requirements of the respective sports as well as allowing for extending the strips beyond the enclosures to create covered outdoor areas that provide shade and shelter from the rain. The repetitive use of the elements creates flexibility, rendering a form that can be easily expanded as needs change in the future. Also, while the four gymnasiums function independently, this topographic “cover,” which calls to mind the landformlike architecture of Peter Eisenman’s City of Culture of Galicia, Spain, enables the entire complex to be read as a whole and, with the protected public zones it creates along the buildings’ peripheries, creates a spatial continuity as well.

Fundamental to the architects’ approach was the idea of creating an open architecture. Laminated metal facades perforated with a delicate, laser-cut leaf pattern respond to the mild local climate (Medellín, after all, is known as the City of Eternal Spring), permitting breezes to enter and condition the spaces. This veil, which shrouds the muscular structure, Mesa points out, “also results in social transparency and accessibility.” Not only can users catch glimpses out to the city while inside, but they also can peer in without entering, enabling them to observe sporting events without having to pay admission. Now that the Games have ended, professional teams, the general public, and schoolchildren regularly use the facilities. “In general, coliseums are closed buildings,” notes Mazzanti. “You can’t see what’s inside. With these buildings you can see everything. This is truly a public place.” Indeed, the covered interstitial areas between the buildings — which are visually a bit cavelike, edged with a mangrovelike forest of steel double columns — have a great democratizing force. In addition to serving as extended viewing areas for sports fans, they encourage pedestrian circulation through the complex (each gym has its own entrance) and host a wealth of both organized and spontaneous activities. On a recent weekend afternoon, the spaces were animated by the movements and sounds of pep squad practices, skateboarders, and team warm-up drills.

In line with the rest of the surrounding sporting complex, the coliseums are arranged along a north–south axis. This siting optimizes cross-ventilation by taking advantage of the predominating northerly breezes, an important consideration for a building that has no central cooling. The orientation also acts in concert with the roof forms, which create giant north- and south-facing clerestories. These apertures, in addition to those at both ends of the buildings, are positioned to block the sun’s glare while admitting a pleasing ambient light through their polycarbonate channel glazing.

A basic material palette reinforces the project’s municipal feel. The floor slabs and precast bleachers are concrete. The architects opted for steel for the structure, facades, and roof. This, combined with modular components fabricated off-site, they reasoned, would speed up construction, enabling them to meet the tight deadline. Light-gauge steel trusses, placed every 16 feet and resting on the double columns that proliferate around the buildings’ exteriors, form box beams that house lighting for the courts. The roof assembly itself consists of a sandwich of fiber cement board, a waterproofing membrane, and bands of metal roofing painted in varying shades of green to echo the tones of the surrounding mountains.

The accelerated pace of design and construction that typify Colombia’s competition system for public work can lead to limited material choices and detailing or compromised construction quality. Yet haste has its advantages as well. In the case of Medellín’s Coliseums, squeezed budgets of time and money caused the architects to focus on form making and social place making. And snap decisions resulted in an immediacy in design and construction, yielding a monumental complex that buzzes with activity and is at once fresh, undiluted, and raw.