They loom on our horizons and dominate our high streets – the spectacular listed buildings that evoke our past.
But many of these beautiful buildings are crumbling away, bereft of a purpose and in desperate need of some TLC.
Some, such as the eyecatching art deco style Bank of Ireland building on Royal Avenue, just need a little attention. Others, such as the stunning Mount Panther house at Dundrum, are far gone, roof missing and interior crumbling away at the mercy of the elements.
The DOE has sent out more than 140 letters to owners of the most at-risk buildings, advising them of their responsibilities.
According to the Ulster Architectural Heritage Society, a lot of owners are stuck in limbo.
Heritage projects officer Lorraine Robinson said: "When a building becomes vacant, it can become vulnerable to the elements and it can also become susceptible to vandalism. There is also the threat of heritage crime.
"If the current owner does not have a sustainable end use or plan in mind, putting the property on the market is a solution that we encourage through the Built Heritage at Risk Northern Ireland (BHARNI) partnership.
"This way it brings a bit of movement to the Buildings At Risk register in the way of getting the building into the right hands of someone who may be in a better position to do something positive. Listed Building Grant Aid is also at 45% at present – the highest it has ever been – again an added incentive for anyone thinking of taking on a listed property."
A Department of the Environment spokesperson said: "The NI Environment Agency's (NIEA) Historic Buildings Unit has recently undertaken a 'prioritisation exercise', to assess those listed buildings which are at most risk from on-going deterioration.
"Following this exercise, 142 letters have been sent out to the owners of these buildings, advising of their responsibilities and the availability of NIEA Listed Buildings Grant-aid, along with advice by NIEA Conservation Architects on 'best practice' conservation strategies.
"This has resulted in a significant level of interest from these owners. In addition, NIEA is aware that a number of listed buildings at risk are being offered for sale and welcomes engagement with new owners seeking to conserve these buildings.
"Since April, 15 structures have been rescued and will be removed from the NIEA Built Heritage at Risk Register. A total of 200 structures have been removed from the BHARNI Register since 2004."