Tre-Gynon Camp

This Iron Age hillfort sits on high ground between Newport and the Preseli Mountains, and it's genuinely atmospheric if you know what you're looking at. The earthworks are still there - two sets of defensive banks and ditches that would have enclosed the settlement proper, though the landscape does most of the talking rather than the ruins themselves. You're essentially walking around a field, reading the lumps and bumps as fortifications, which either appeals to you immensely or leaves you cold depending on how much Iron Age Wales matters to you.

Army types and archaeology enthusiasts will spend a solid hour here picking out the defensive strategy. Anyone else will manage half that and probably feel they've got the measure of it. The real draw is the walk itself and the views across Pembrokeshire from the top - on a clear day it's proper rewarding, and on a grey one it feels appropriately moody for a 2,000-year-old military installation.

There's no visitor infrastructure to speak of, and access is straightforward enough if you know where to look. The nearest base would be Newport itself, which is handy for Llwyngwair Manor or one of the Trewrach options if you're staying at the holiday parks. Good for a morning ramble before heading to the beaches or other Preseli attractions, but don't expect signage or facilities. Bring sensible shoes and weather-proof layers.