Spahill and Clomantagh Hill is a Special Area of Conservation (SAC) in County Kilkenny, Ireland.

The SAC is in the parish of Balleen and includes the townlands of Clomantagh (Mt Garrett) and Spahill, in Irish Spahill is Cnoc na Spá[2] and Clomantagh Hill is An Chloch Mhantach.

Spahill is mostly limestone which is exposed in ledges and flat sheets and Clomantagh Hill has a geology which is quite similar to that of Spahill but the summit has an exposure of the overlying sandstone, this looks different from the limestone as it appears as low rocks.

Over the sandstone at the summit of Clomantagh Hill there is a markedly different flora which includes more ling and other plants more typical of heaths.

The SAC contains some woodland to its north west, mainly of downy birch and hazel which has a rich ground flora.