Archiseek
Summary histories of important Irish buildings, including sections on counties Monaghan, Fermanagh and Tyrone. Includes some information on minor houses.

Ulster Architectural Heritage
Ulster Architectural Heritage promotes the appreciation of architecture from the prehistoric to the present in the nine counties of Ulster, and encourages its preservation and conservation.

An Taisce
An Taisce - 'The Store House, or Treasury' is The National Trust For Ireland. Established in 1948, it is the most influential environmental body in Ireland.

Irish Historic Houses Association
Incorporated as a company with charitable status in 2008. Works for the preservation of Ireland's remaining historic houses, for Ireland's cultural heritage.

Irish Landmark Trust
The Irish Landmark Trust is a charitable organisation founded in 1992 that saves heritage buildings at risk of being lost through neglect or inappropriate intervention. We then give the buildings a future by letting them for self catering holidays in Ireland.

National Inventory of Architectural Heritage
Gives a list of important buildings in County Monaghan with OS references, bibliography, map images and aerial photographs for each.