Hostile architecture

Hostile architecture is designed to limit loitering, sleeping, and other unwelcome behavior in public spaces. Such architecture might include spikes, bars, railings, and other obstructions on seating. It includes benches that are slanted, segmented, or curved. Boulders lining the pavement under a bridge or a city sidewalk are also elements of hostile architecture. Proponents of the technique also call it defensive design. 

However, critics, who have grown more vocal in the twenty-first century, contend that a more accurate term is anti-homeless architecture because the designs disproportionately target vulnerable populations during a time when many urban areas are facing a homelessness crisis. They claim that hostile architecture refers to any design features explicitly created to deter people experiencing homelessness from finding somewhere to sleep or teenagers looking for somewhere to play or loiter.

Background

Since at least 2010, hostile architecture has raised debate, even if the term was not widely used. At that time, Richard Goloveyko’s metalworks firm Veyko designed curved metallic benches for Philadelphia’s subway stations, admittedly with homelessness and other urban issues in mind. According to Goloveyko, the challenge was to create an evocative form while considering defensive stances. The subway station in Philadelphia did not want people lingering on the platform for extended periods, and a major metropolitan subway station is not a park or an outdoor space. Though his benches were later tagged as hostile, Goloveyko contended they remained an interesting, well-used, and comfortable form that had withstood the abuse of millions of public commuters and were not threatening.

In 2012, in Charlottesville, Virginia, public benches were removed entirely from the downtown mall, a multi-block strip of stores and public space. Some called the move a defensive design to deter panhandling and loitering. Architect and city councilor Kathy Galvin said the inherently public space could not be exclusive, but, at the same time, her duty as a public servant was to protect her constituents’ safety. As an offset to the bench removal, the city was attempting to improve its outreach for vulnerable populations with more inclusive programming and investing more in affordable housing, job creation, and apprenticeships. Critics believe that such balancing efforts are not enough to counter the effects of hostile architecture. They believe that the problem with this architecture is that it does nothing to address the root problems of homelessness.

By 2015, when retailers in the United Kingdom (UK) installed metal spikes around their entrances, hostile design was making headlines across the world. And by 2018, the hashtag #hostilearchitecture was trending on social media, accompanied by photos of park benches with armrests down the middle and sprinklers engineered in public spaces to water squatters rather than greenery.

Overview

A highly controversial topic in urban design, hostile architecture includes aspects that both recommend and discourage it. Proponents say maintaining order and cleanliness in public spaces is highly justifiable, but critics rail against the underlying intention of excluding and displacing unhoused populations.

Some examples of hostile architecture are more extreme and intentional than others. For example, spiked or rocky pavement, particularly under awnings or other shelters, or barred corners are designed specifically to prevent sleeping, while street dividers such as obstructive planters are meant to push people experiencing homelessness away from the sheltered side of a street. Raised grate covers or fenced grates are intended to prevent sleeping on heat-emitting grates to stay warm in winter. Retractable spikes, which can be pushed up at night to prevent people from sleeping outside store premises without making shoppers uncomfortable with defensive design during the day, are another example of the extremes of hostile architecture.

Hostile bench designs throughout the world have run the gamut from tubular structures that get very hot in summer and icy cold in winter to benches that are far too short for anyone of average height to lie across. These designers have also experimented with pay-to-sit benches that release a small spike once the allotted time is up and benches that get folded up and locked at night.

Critics contend that attacking unhoused individuals with spikes is morally akin to assault, and designers should not be allowed to incorporate the threat of pain into the built environment. They believe that designers have an ethical responsibility to refuse to create anything meant to inflict pain on people experiencing homelessness for attempting to sleep, considering the duty to be as basic as the moral obligation not to commit offensive violence. 

Critics note that a key problem is that some hostile design choices are not obvious but exist as an absence, such as a failure to provide benches, bathrooms, or shady places. “Ghost amenities” are the water fountains and picnic tables that a space lacks because designers have decided that any place fit for human beings will be fit for people experiencing homelessness. It is not enough to simply remove the spikes when designers create desolate public spaces where nobody can rest. The failure to build public spaces at all is also hostile because it means that only the advantaged will have comfortable places to go.

Critics lobby for public spaces that welcome people and care for their needs, regardless of whether that results in places becoming full of people who do not have a place to sleep. If that happens, society must choose between ruining public spaces with hostile design or caring for everyone compassionately and making universal design—places that meet everyone’s needs—a priority.

Opponents of hostile design claim that the real challenge is to build compassion and care into every space. While this need is being met, they suggest getting rid of the features that directly physically assault people who are experiencing poverty, tiredness, and illness. Some regions have passed laws preventing hostile design. In 2023, a law went into effect in Brazil designed to prohibit hostile architecture in public spaces. In the US, a bill was introduced in Massachusetts in 2025 that aimed to ban hostile architecture designed to prevent unhoused individuals from sitting in public spaces.

However, hostile architecture is not exclusively designed to deter unhoused populations and is not necessarily a physical impediment. To deter intravenous drug use, public restrooms in Victoria, British Columbia, installed blue lights, which obscure superficial veins. Studies have shown, however, that drug users will still try to inject themselves in blue-lit bathrooms and incur increased risk of infection and soft tissue damage. Critics also point out that blue light hinders safety for all bathroom users by reducing visibility and making it harder to clean up bodily fluids. Even birds have been targeted. Metal spikes placed in tree branches have cut down on droppings in public spaces while rendering trees uninhabitable for winged creatures.

On the other side of the debate, those who eschew the term "hostile architecture" in favor of "defensive design" claim that it serves the dual purpose of protecting local economies and increasing safety in public spaces, or, at minimum, perceptions of safety. The pressure for city officials to maintain and protect the appearance and safety of infrastructure is real, they note, especially for cities that heavily rely on tourism. By manipulating the built environment, planners encourage consumers to spend money while discouraging people they do not want to cohabit the space.

However, as the aesthetics of city streets evolve, planners and designers have begun to implement newer, more discreet forms of hostile architecture that are also less exclusionary. Most notably, cities have begun integrating new technology into defensive design. Blue light bathrooms would fall into this category, though they also present their own moral challenges, as previously noted.

Sound-based defensive design, such as the “Mosquito,” which emits a high-frequency sound most audible to teens and young adults, has also been employed. While not bothersome at first, after a few minutes, this sound becomes intolerable. Critics believe this sound-emitting technology is unnecessarily aggressive and endangers community relationships.

Newer technologies have continued to prompt many community and industry discussions about the rights of citizens versus those of private businesses and the duty to protect safety versus the duty to care for all humanity.

Bibliography

Hu, Winnie. “Hostile Architecture: How Public Spaces Keep the Public Out.” New York Times, 14 Nov. 2019, www.nytimes.com/2019/11/08/nyregion/hostile-architecture-nyc.html. Accessed 12 July 2023.

McFadden, Christopher. “15 Examples of ‘Anti-Homeless’ Hostile Architecture Common to Cities.” Interesting Engineering, 8 Apr. 2023, interestingengineering.com/culture/15-examples-of-anti-homeless-hostile-architecture-that-you-probably-never-noticed-before. Accessed 12 July 2023.

Robinson, Nathan J. “Hostile Architecture Is Evil and Should Be Banned.” Current Affairs, 17 Aug. 2022, www.currentaffairs.org/2022/08/hostile-architecture-is-evil-and-should-be-banned. Accessed 12 July 2023.

Ruetas, Faith. “15 Examples of Hostile Architecture around the World.” Rethinking the Future, www.re-thinkingthefuture.com/designing-for-typologies/a2564-15-examples-of-hostile-architecture-around-the-world/. Accessed 18 Feb. 2026.

Tsavkko Garcia, Raphael. "One Year Ago, Brazil Banned Hostile Architecture. Easier Said Than Done." Next City, 30 Dec. 2024, nextcity.org/urbanist-news/one-year-ago-brazil-banned-hostile-architecture.-easier-said-than-done. Accessed 3 Feb. 2025.

Wallace, Elizabeth. “What’s Behind the Uptick in Hostile Architecture?” Architectural Digest, 21 Mar. 2018, www.architecturaldigest.com/story/hostile-architecture. Accessed 12 July 2023.

Wiseman, Eva. "Hostile Architecture Is Making Our Cities Even Less Welcoming." The Guardian, 21 Jan. 2024, www.theguardian.com/lifeandstyle/2024/jan/21/hostile-architecture-is-making-our-cities-even-less-welcoming. Accessed 18 Feb. 2026.