On a graffiti-stained sidewalk in Paris<\/a>, a strange sight appeared days before the Olympic opening ceremony<\/a> in July: Around 40 giant cement Lego-like blocks in neat rows beneath the Pont de Stains, a bridge in the northern suburb of Aubervilliers that connects two Olympic sites, the Stade de France and the Parc des Nations.<\/p>\n This place used to be a homeless encampment, where around 100 people, many of them migrants, lived in tents. Then on July 17<\/a>, the police arrived and instructed everyone to leave<\/a>, as part of a cleanup operation in which authorities put homeless people, members of the Roma community, migrants, and sex workers on buses<\/a> to other cities, such as Bordeaux or Toulouse.<\/p>\n Once the authorities emptied the area, according to activists, the immovable blocks of concrete were installed in place of the tents, ending any notion the former residents may one day be able to return.<\/p>\n Campaigners say these bricks are an example of hostile architecture, a term used to describe some of the most visible changes cities and companies make to deter homeless people loitering or sleeping on their properties. \u201cThis is not new, but it has been intensified in a very specific way during the Olympics,\u201d says Antoine de Clerck, part of Le Revers de la M\u00e9daille, a group of activists raising awareness of how marginalized people are treated during the Olympic Games.<\/p>\n \u201cWe do not advocate for encampments and squats and shantytowns,\u201d adds de Clerck. \u201cBut to eradicate them, you have to find alternative long-term solutions.\u201d<\/p>\n Despite other examples of hostile architecture in Paris, including picnic tables<\/a> installed where people used to sleep, it is the giant Lego-style blocks that have proved most controversial. \u201cI haven\u2019t seen anything quite like this,\u201d says Jules Boykoff, a professor and former professional soccer player who studies the impact of the Olympics on marginalized communities. \u201cTypically, hostile architecture is more subtle,\u201d he says, \u201clike a curved bus bench that makes it less comfortable for somebody to sleep.\u201d<\/p>\n![\"Metal](\"https:\/\/media.wired.com\/photos\/66b3e96a812fe9ff6e7d6aa0\/master\/w_1600%2Cc_limit\/GettyImages-1040601444-sm.jpg\")