More than 130 security bollards are being erected around the courthouse in Londonderry three weeks after an attempted dissident republican car bomb attack on the building.
The move has disappointed tourism chiefs and politicians who feel it is sending out the wrong message about the city.
Thirty-six gas activated pop-up pillars and 90 fixed bollards are being installed outside the building. The barriers run from just inside the city's historic walls to St Columb's Court, a distance of about 50 metres.
The move follows the discovery of a car bomb in a car park opposite the courthouse last month.
The device contained 200lbs of explosives and was defused by Army bomb disposal experts following a number of controlled explosions.
The alert caused widespread disruption for several hours on March 28 when the elderly residents of a sheltered housing development had to be evacuated to a nearby hotel and choirboys rehearsing for the opera Tosca in St Columb’s Cathedral were told to leave for their own safety.
At the time, PSNI chief Steven Martin said that had the device exploded it would have caused “considerable devastation”.
Tour guide and city centre businessman Martin McCrossan described the installation of the bollards as a backward step, while laying responsibility for the move firmly at the feet of dissident republicans.
Speaking to the North West Telegraph, Mr McCrossan said: “I asked the Northern Ireland Office not to do this because it would send out all the wrong messages, but I appreciate that the police have a duty to protect life and limb and that the fault for this lies with the dissidents.
“I fully understand and respect their decision and I would hate to think that something would happen because the bollards were not there, but we are living in largely peaceful times and I am confident that people will not be deterred from coming to Derry.”
MP for Foyle, Mark Durkan, whose constituency office is just a few metres from the courthouse, was equally critical.
“While the bollards are not too obtrusive, they will detract from the streetscape on an important part of the tourist trail in The Walled City,” he said.
“This diversion of resources is just one more example of the disruptive impact of the violent efforts of so-called dissident groups.”