Carrickfergus Castle

The medieval fortress looming over Carrickfergus Harbour is impossible to miss - a proper Norman keep that's been standing guard since 1177. You're looking at one of Ireland's oldest castles, its craggy stone walls rising straight from the waterfront, with the kind of views across Belfast Lough that justify the walk up to the battlements alone.

Inside, the castle's split across an outer ward and inner keep, with exhibits covering everything from its role in the 1690 siege through to its time as a military barracks. The walls themselves tell the story - you'll see where cannonballs hit, the murder holes above the gatehouse, the garrison chapel tucked into the curtain wall. It's genuinely atmospheric rather than touristy, which works brilliantly if you've got a taste for proper military history. Kids will burn off energy running the ramparts, though the tight spiral stairs might test younger legs.

Allowing two to three hours gives you time to explore both levels without rushing. The castle sits right on the waterfront near Larne, making it a natural stop if you're heading along the coast - pair it with a stretch along the harbour foreshore or a night at Down to Earth Wild Camping just five miles out if you want to stay local.

Autumn and early spring are when it feels least crowded, though frankly the place has enough atmosphere that even a grey day adds to the charm.