The Army has begun dismantling its observation post on the top of Divis Tower flats in west Belfast.
Soldiers work at the top of the 19-storey Divis tower (Army picture)
It is part of a two-year programme to scale down security in the province after last week's IRA statement saying it was ending its "armed campaign".
Soldiers went onto the roof of Divis Tower on Tuesday and began taking down the equipment that looks over the whole of west Belfast.
Sinn Fein's Gerry Adams said no one should worry about the speed of events.
"The British army should never had been here at all and they served no useful purpose here on Divis Tower," said the West Belfast MP.
"We are told that it was there for our protection but people were killed in my constituency office, people were killed in this neighbourhood, all within sight of the squaddies on this tower."
The work at Divis Tower is likely to take months to complete.
The three Army figures working on top of the tower could be seen for miles around.
Soldiers work at removing equipment on Divis tower (Army picture).
The controversial observation post - dubbed a "spy" post by republicans - was first installed in the 1970s.
By the late 1980s the Army had taken over the top 19th and then the 18th floor.
In recent years the housing executive has spent millions renovating Divis Tower - once the observation post is completely dismantled, there will be 10 new flats ready for tenants to move in.
On Monday, the camera at the top of the Army observation tower at Creevekeeran near Crossmaglen in south Armagh was removed.
Work also started on the dismantling of three other security posts in the area at the end of last week.