Visitors to popular landmarks across Australia have been confronted in recent weeks by the sudden appearance of a series of concrete barriers that have been described as a stark reminder of the new era of terrorism.
The authorities said the slabs and bollards, placed at sites such as Sydney's Martin Place and Melbourne's Federation Square, were designed to prevent attacks such as those in Nice, London and Berlin in which terrorists used vehicles to mow down pedestrians, killing scores of people.
But the slabs have prompted concerns among some locals that their city is starting to resemble a "fortress". Accepting the criticism, state and city governments insisted the measure was necessary and signalled they will beautify the barriers as soon as possible.
At Melbourne's Southern Cross rail station, where more than 50 bollards popped up last Thursday night, residents greeted the structures with a mixed response. Some said they accepted the need for the security measure, but others questioned the impact on the city's aesthetics.
"What next - barbed wire? It doesn't look good at all," a city worker, who gave his name only as Jean, told The Age newspaper.
A columnist for the newspaper, Mr Mark Holden, said the square concrete bollards were not merely brutal and ugly but were a "depressing" reminder of the constant threat of terrorist attacks.
The State Government of Victoria has placed A$10 million worth of concrete barriers - about 140 in total - at nine locations around Melbourne's city centre.
The State Government of Victoria has placed A$10 million (S$10.2 million) worth of concrete barriers - about 140 in total - at nine locations around Melbourne's city centre.
The precaution followed a horrific incident in which a man drove a car into crowds in Melbourne's Bourke Street in January, killing six people and injuring more than 30. The alleged killer, Dimitrious Gargasoulas, 26, described himself as "a Saviour" and blamed the incident on the "illuminati".
Counter-terrorism experts supported having these barriers, saying they were a worthwhile form of "proactive" security and could help to deter attacks.
Professor Geoff Dean from Griffith University's Criminology Institute said concrete blocks were an effective security measure but noted that "you can have protection without it being ugly". He told The Straits Times that the authorities could place large objects such as flower pots rather than concrete blocks, adding that "security and landscaping can go hand in hand".
"Bollards and concrete slabs will limit the access of a truck or a vehicle to a crowded place. You can have security with beauty - you can build security into the landscape so that it is attractive."
In Sydney, the authorities began installing concrete blocks last Friday in Martin Place, the scene of a deadly siege by an Islamist militant gunman in December 2014. The first of the blocks were placed on the pedestrian strip near the Lindt Cafe, the site of the siege.
New South Wales state Counter Terrorism Minister David Elliott said further bollards would be placed at other popular spots where there is heavy foot traffic.
"There is no specific threat but the likelihood of a lone wolf-style attack is an unfortunate reality," he told Sydney's Daily Telegraph newspaper.
"Major cities like Sydney will need to prepare themselves for this sort of inconvenience."
Barriers are also being placed at iconic sites around Australia, including metal fencing that now prevents access to the lawns around Parliament House in Canberra.
The city councils in Sydney and Melbourne said they plan to eventually replace the bollards with more eye-pleasing features such as garden beds or street furniture.
"We'll look first at street furniture, planter boxes and rubbish bins, which can be reinforced and turned into unobtrusive but effective safety measures," Melbourne's Lord Mayor Robert Doyle told news.com.au last Saturday.