Castell y Geifr

The walk up to Castell y Geifr rewards you with one of those views that makes the effort genuinely worthwhile. You're looking out across the Menai Strait towards Anglesey, with Snowdonia's peaks rising up behind you - it's the kind of vista that justifies the leg-burning climb.

It's not a difficult hike, but it's steep enough that you'll feel it. Most people allow an hour to get up and down, though if you dawdle at the top - which you will - add another thirty minutes. The "castle" itself is really just rocky outcrops and a modest stone structure, nothing grand, but the location is what counts here.

This works brilliantly if you're based at one of the caravan parks around Llanberis or Llyn Gwynant - both within easy driving distance - and you fancy a half-day activity that doesn't require booking or paying entry fees. Walkers will eat this up. Families with younger kids might find it a bit much unless they're proper little hikers already.

Bangor's the nearest town if you need supplies or somewhere to eat afterwards. The weather matters hugely - on a clear day this is magic, but cloud cover rolls in fast around here, so check the forecast before heading out. Winter can make the path slippery, so boots are essential. Go in autumn when the light's golden and the crowds have thinned out - that's when it's at its best.