Have you heard of a half house? Been poked by a church made of cacti? Taken a stroll through a university with a wide-open addition? If any of these architectural features surprise you, you need to take a closer look at this list of the five buildings you need to see in Chile.

　　Earlier versions of the descriptions of these buildings first appeared in 1001 Buildings You Must See Before You Die, edited by Mark Irving (2016). Writers’ names appear in parentheses.

　　The ESO Hotel crouches in the Atacama Desert, where the red land, littered with shards of stone and mounds of gravel, resembles a Martian landscape. The desert is sunbaked during the day, temperatures plummet at night, and winds sweeping in from the Andes toward the Pacific blast the unforgiving terrain. Architect Philipp Auer had to consider these factors in his design, in addition to considering how to limit the visual impact of a building in such a remote location. When faced with the constraint of limiting light emissions from the building, Auer brought in lighting designer Werner Lampl, who designed a complicated illumination system that runs throughout the building.

　　Though the word “hotel” suggests groups of tourists coming and going, the ESO Hotel is in fact a private relaxation facility for the astronomers who visit the European Southern Observatory and a permanent residence for the engineers and scientists who work on the site. The scientific facility is located on a high peak and looks down on the ESO Hotel, which, to minimize light pollution, is snuggled in a desert hollow at the foot of the incline. The success of the structure lies in its simplicity: a series of concrete modules set low to the ground. Behind the concrete block retaining walls lies a geodesic dome of polycarbonate sheeting, housing a courtyard and the swimming pool. Judicious planting here minimizes the effect of low humidity and tempers the rays of the sun. The dome is the only part of the building that rises above the horizon. The concrete used for construction was mixed with iron oxide to match the russet earth in which the structure sits, allowing it to blend in with the terrain. The ESO Hotel, completed in 2002, is an eloquent example of symbiosis between the natural and the built environment. (Jennifer Hudson)

　　This ambitious social housing project in Constitución, built in 2013, is another development in a route followed by the founder of Elemental, Alejandro Aravena, who first came up with the idea of designing “half houses” in his project Quinta Monroy. The idea is to design houses for people with little money by building part of the house and leaving a gap that they can later fill in themselves. This not only allows them to make additions for an expanding family but also lets them determine the form that the extensions will take to suit their particular needs. What starts off looking like a uniform row of houses becomes a collection of individual buildings bound by a common underlying structure.

　　The essence of these housing developments is their low cost, but the Villa Verde housing complex, intended for workers of the forestry company Arauco, was of such generous dimensions that Elemental was able to improve on the specification, thanks to the economies of scale. The first phase consisted of 484 houses and three community centers.

　　The base build, which occupies one side of the pitched roof enclosure, consists of a small shared space on the ground floor comprising a kitchen, dining area, and living room, plus a bathroom and an external laundry space. On the first floor there are two bedrooms and another bathroom. Since all the core services, including the staircase, are included in the base build, owners should be able to extend into the void without needing very sophisticated skills.

　　The buildings are constructed as timber frames supported on concrete foundations. Roofed in zinc, they are clad internally in gypsum board and externally in fiber-cement board. (Ruth Slavid)

　　San Pedro de Atacama ChurchSan Pedro de Atacama is a pre-Inca town situated around an oasis in northern Chile’s Atacama Desert, which is the driest desert in the world. Visitors generally stop there in order to visit the surrounding natural wonders, including the desert’s salt flats. The Spanish conquistadors settled in the area in 1540 and evangelized the locals. The town’s population today consists of descendants of the Atacama people. The majority of the population is Roman Catholic, and San Pedro Church, named after the town’s patron saint, is a popular place of worship. The church is located on the west side of the central square and is surrounded by ancient pepper trees. It was built in 1774, replacing an existing one built in the 17th century, and is one of the oldest churches in Chile. Built of stone and adobe, the church has a cross-shaped ground plan, with a nave measuring 134 feet (41 meters) long by 25 feet (7.5 meters) wide. What is most remarkable is the use of cardón cactus wood in its construction. These 33-foot- (10-meter-) high cacti are used to build houses in the area. Cactus is used for the door at the main entrance, and leather straps are used instead of nails. The roof framework is made of local woods, and the ceiling is constructed from small cactus boards, mud, and straw. An adobe bell tower was added in 1964, to replace a previous one built of wood. Inside, there is a richly decorated carved stone reredos screen behind the high altar. (Carol King)

　　In a profession where architects in their 50s are still considered to be “emergent,” Mathias Klotz represents an astonishing exception. Immediately after graduating from university in 1991, he was able to get direct commissions without the customary internship in some other architect’s office. In a country that is 3,000 miles (4,828 km) long and has just 15 million people inhabiting it, space is in abundance. Consequently, the Chilean middle class has provided architects such as Klotz with plenty of opportunities to build their second homes.

　　Casa Vieja, built in Santiago de Chile in 2002, injects new interest into schemes first adopted by the architects of the Modernist movement. Although the exterior of the house follows the Modernist tradition by providing two long plates for the roof and floor of the villa, Klotz introduces subtle alterations to adapt it to local conditions. Here the pure abstraction of European Modernism is “contaminated” by a rich, warm palette of local materials ranging from rough concrete to wood. Klotz has morphed the geometric precision of avant-garde architecture to achieve specific spatial effects, as seen in the sequence of spaces that lead to the entrance of the house. He creates a spatial compression by first lifting the path to the house through a ramp, which then slips under two cantilevering platforms clad in wood to finally lead to the narrow entrance door. The rear elevation has a long, generous opening that not only brings light into the four bedrooms but also opens up onto a wooden deck facing the swimming pool. Casa Vieja represents an important step in Klotz’s search for simple, clear solutions and is unique in its specific use of materials and exploitation of the relationship between the architecture and the landscape. These efforts were acknowledged in 2001 when Klotz was awarded the Francesco Borromini Award for Young Architects. (Roberto Bottazzi)

　　School of Architecture, Universidad Técnica Federico Santa MaríaThe School of Architecture at the Universidad Técnica Federico Santa María in Valparaíso is an award-winning project that represents one of the first architectural structures designed by a generation educated using both computers and traditional forms of representation, such as drawings and models. The project’s tight schedule and limited budget were incorporated into the process, turning them from constraining elements into design possibilities. Rather than housing the program in a series of separate and independent rooms, Lang Wilson Practice in Architecture Culture tried to build into the design an idea of incompleteness by proposing a large undefined open space where several activities can take place. Students and teachers are invited to interact with the building, to take ownership of it, and to determine where and when activities will happen. Ramps, double volumes, and mezzanines are the architectural elements that make interaction between the architecture and its users possible.

　　The 8,500-square-foot (790-square-meter) new space floats on top of the existing school and is defined by a continuous metal roof that compresses and dilates the internal spaces. The skin of the building is partly covered by louvers that control the environmental conditions. In fact, this building, finished in 1999, does not have an air-conditioning system but relies on natural ventilation alone. Beyond the deep conceptual reasons of the project, to visit the school is to experience a modern, daring piece of contemporary architecture. (Roberto Bottazzi)