Pen Llystyn Roman Fort

The Roman fort at Pen Llystyn sits on high ground above Garndolbenmaen, a quiet corner of Gwynedd that most visitors skip entirely. What you'll find is less dramatic than Segontium or Caernarfon - this is archaeology stripped back to foundations and earthworks, the sort of place that rewards a bit of imagination. The fort dates to around 75 AD, built to control the local roads and keep an eye on the Snowdonia tribes. Today the site consists of low grass-covered banks marking the perimeter, along with some internal features if you know what you're looking at.

This isn't a day-out destination on its own. There's no visitor centre, no interpretation boards to speak of, and you'll need decent map-reading skills or a good phone signal to find your way around. Archaeology enthusiasts will get something from it - the layout is readable enough if you've done a bit of Roman fort spotting elsewhere. Families with younger kids might find it underwhelming after twenty minutes. The walk up is gentle enough, and you do get decent views across the landscape once you're there.

If you're based at one of the camping parks dotted around the Cardigan Bay coast - Black Rock Sands, Aberafon, or Haven Hafan y Môr are all within striking distance - it makes a reasonable rainy-day excursion when the beach isn't appealing. Give it an hour, max. It's free, accessible year-round, and the surrounding countryside is worth the drive regardless.