Carrowkeel Passage Tomb in Sligo is an extensive Neolithic passage tomb undisturbed its excavation in 1911.
Robert Praeger, one of the excavators, described being one of the first to enter the tomb: 'I lit three candles and stood awhile, to let my eyes accustom themselves to the dim light.
There was everything, just as the last man had left it, three to four thousand years before.' On an isolated hillside the tomb is in almost the same undisturbed condition today.
Ireland is rich in such monuments and buildings that preserve the stamp of the past.
Here, Tarquin Blake and Fiona Reilly explore and document 150 Irish heritage sites across the thirty-two counties.
These range from megalithic tombs to round towers, monasteries, castles and ancient churches to the more recent Martello towers and windmills.
An engrossing catalogue of remarkable heritage sites is revealed.
Each site has an intriguing past and is illustrated with Blake's trademark photographs.
Maps and GPS co-ordinates make these sites accessible to the public, from Brian Boru's Fort in County Clare to Moyne Friary in County Mayo.