Maes-y-Gaer Hillfort

Standing stones mark the entrance to this Iron Age hillfort, perched high above the Menai Strait with proper views across to Snowdonia. The ramparts are still clearly visible after 2,000 years - impressive earthworks that curve around the hilltop in a rough oval. You'll need sturdy boots for the climb up from Llanfairfechan, but it's well worth the effort once you reach the top.

History buffs will love exploring the defensive banks and trying to imagine life here when the Celts ruled this corner of Anglesey. The site feels genuinely ancient, especially on a misty morning when you can barely make out the mainland peaks. Kids might find it a bit abstract unless they're already into castles and old stuff.

Allow a good hour for the walk up and back, plus time to poke about the ruins. It's free to visit and always open, though the path can be slippery after rain. The views alone justify the trek - you get the full sweep of the coast from here.

If you're staying at one of the holiday parks near Llanfairfechan like Three Streams Glamping or Craiglwyd Hall, this makes a decent half-day adventure. Combine it with a trip into the town afterwards for supplies or a proper Welsh tea.