The Gwaun Valley Woodland Walk

Cwm Gwaun is one of the odder places in Wales, geologically and socially. It's a glacial meltwater channel — carved by torrents of water escaping from beneath the ice sheet at the end of the last glaciation — which is why it's a deep, steep-sided, flat-bottomed valley containing a river far too small to have made it. It runs from the Preselis down to the sea at Fishguard, and it feels entirely enclosed.

Start at the Sychpant picnic site, where there's a free car park, tables and waymarked trails through the woods. The route drops to the Afon Gwaun and follows it upstream through some of the best ancient sessile oak woodland in Pembrokeshire: mossy, lichen-hung, low-canopied Atlantic oak wood of the sort that has largely disappeared from lowland Britain. The bluebells in late April and early May are the main event; wood anemone, wood sorrel and ramsons come before and with them.

Watch the river. Dippers work the stones — dark birds with white bibs that walk underwater — and grey wagtails are common. There are otters, though seeing one takes luck and an early start. Pied flycatchers and redstarts breed in the woods in summer.

The path climbs gently out of the trees to give you a view up and down the valley before dropping back through the woods to the picnic site. There are short steep bits and a few sets of steps, but nothing that counts as hard work.

If you have longer, extend along the valley to Pontfaen, where there's a small church with early Christian inscribed stones in the churchyard and a pub that has been serving the valley for a very long time.

The valley's real claim to fame is calendrical. When Britain switched from the Julian to the Gregorian calendar in 1752, Cwm Gwaun didn't, and the community still marks Hen Galan — the old New Year — on 13 January, with children going round the houses singing for money and sweets. It is not a re-enactment; it never stopped.

Where to eat. The pub at Pontfaen if it's open — the hours are its own business, so don't build the day around it. Fishguard is fifteen minutes down the valley and has proper choice.

With children. This is one of the better easy walks in the county: short, sheltered from the wind, a river to poke about in and a picnic site with tables at the start and finish.