The Discovery of Loughcrew
It is astonishing, given its geographic prominence and the extent of its monuments, that John O’Donovan and the other meticulous investigators of the Ordnance Survey in the 1830s gave but scant attention to Sliabh na Caillíghe.9 Eugene A. Conwell undertook the first thorough exploration and mapping of the hilltops after he happened upon them during a picnic with his wife in 1863.