Castell Odo

You're looking at the remains of a medieval castle that commands views across the Cardigan Bay coastline - proper windswept stuff, especially if you've picked an afternoon when the Irish Sea gets restless. Castell Odo sits on high ground near Pwllheli and amounts to earthworks and stone foundations, so this isn't a castle you can walk through. What you get instead is the archaeology itself: the lumps and bumps in the landscape that tell you where walls once stood, where defenders once watched.

History buffs will find it rewarding if they've got the patience to read the site and imagine what stood here centuries ago. It's not a destination that'll keep young children occupied for more than twenty minutes, though the views alone make the walk worthwhile. The real appeal is combining it with a coastal ramble - you're close enough to Pwllheli to make this part of a proper day out rather than a standalone trip.

The site is free to access and there's no formal opening hours to worry about, which means you can visit whenever suits you. Allow an hour if you're walking from the nearby camping and glamping spots - Treheli Farm is only 3.3 miles away, or Glampio Coed Glamping at 1.5 miles if you want something closer. Both make sensible bases for exploring this stretch of the Llyn Peninsula. The walk itself is decent exercise on undulating terrain, so bring proper boots if the ground's wet.