Percey Bysshe

A scramble down the coastal rocks near Newcastle leads to this sea cave that's been carved from the granite by centuries of Atlantic storms. Percey Bysshe Cave sits beneath the dramatic cliffs of the Mourne coast, accessible only at low tide when you can pick your way across the slippery boulders to reach the entrance.

Inside, the cave extends back about 30 metres into darkness, with water dripping constantly from the ceiling and pools reflecting what light filters in from outside. It's properly wild - no safety barriers, no visitor centre, just raw County Down coastline at its most elemental.

Families with young children should probably give this one a miss unless the kids are confident rock scramblers. The approach requires decent footwear and a good head for heights, plus you'll need to time your visit with the tide tables. Adventure-seeking teenagers and outdoor types will love the slightly risky feel of it all.

The cave makes a good addition to a coastal walk from Newcastle, though don't expect to spend more than 20 minutes here unless you're planning to explore the wider shoreline. Several holiday parks around Annalong and Newcastle put you within easy striking distance, making this a proper off-the-beaten-track excursion from your base in the Mournes. Just don't forget a torch if you want to see anything once you're inside.