At the small village of Clarina past Mungret on the N69, hang a right to head north for around 1.5km to the crossroads, before turning left and you'll see, high up on a ridge, the haunting ruin of Carrigogunnell Castle, destroyed in the 17th century. A road to your right heads past the castle, beyond the hedgerow and the fields. The ruins famously adorn the back-cover of U2's album The Unforgettable Fire . It's quite a sight against the skyline at twilight.