Carmarthenshire is proper dog-walking country — National Trust parkland, working forest, a castle on a riverside path, and a coastal park that runs for miles. We’ve already covered the county’s water-safety picture in our separate swimming spots guide, so this one is about walking routes on dry land, checked against what each site actually says about dogs. For the rest of the county’s dog services, see our Carmarthenshire hub page.
Verified walks
Dinefwr Park & Castle, Llandeilo
At Newton House, Llandeilo, Carmarthenshire, SA19 6RT (Google Maps, National Trust’s own page), dogs must be kept on a lead at all times across the parkland, with waste bagged and binned. Only assistance dogs are permitted in the Deer Park and on the boardwalk, because of the White Park Cattle herd and fallow deer that graze there. The parkland itself is free to enter dawn to dusk; Newton House, the garden and café need paid admission. Parking is £6 a car, free for Blue Badge holders and National Trust, Wildlife Trust South and West Wales, or Cadw members.
Pembrey Country Park, Burry Port / Llanelli
At Pembrey, Llanelli, Carmarthenshire, SA16 0EJ (Google Maps), waymarked paths run through pine forest and dunes onto Cefn Sidan beach, with a full route of around 8.6 miles or shorter 1-2 mile loops near the visitor centre. A roughly one-mile stretch of the beach near the main entrance has a seasonal dog ban from May to September, though most of the beach stays open to dogs year-round. Keep dogs under control near the ski slope and play areas; there’s a dog water point and waste bins on site.
Brechfa Forest (Tower site), near Carmarthen
At postcode SA39 9EJ (Google Maps, NRW’s own page) — NRW itself notes this postcode covers a wide area and won’t take you directly to the entrance, about 14.5 miles north-east of Carmarthen via the A484 and A485 — Brechfa Forest has several marked trails, including the Marlais Valley Walk (2.3 miles, following the Afon Marlais). At the time we checked, NRW’s own page stated that all the walking trails here were closed, so check the current status directly with NRW before you set off. NRW doesn’t publish a specific dog rule for the site beyond general visitor safety guidance.
Carreg Cennen Castle, Trapp, Llandeilo
At Trapp, Llandeilo, Carmarthenshire, SA19 6UA (Google Maps, Cadw’s own listing), two dog-friendly trails lead to and around the castle — a longer red-signed route up to the castle itself, and a shorter yellow-signed route along the River Cennen. Dogs should be under close control or on a lead, with sheep and cattle grazing the hillside. At the castle, dogs on short leads are welcome on the ground-floor levels only.
Sir John’s Hill Walk, Laugharne
Starting from Laugharne Castle car park (Google Maps) — which can flood on the highest tides, so check conditions — this 2.6km route along the Taf estuary (not the Towy/Tywi estuary covered in our swimming guide) is on lead, with a maximum of three dogs per person. It’s hillier than the shorter “Dylan’s Walk” alternative from the same town, with a short flight of steps and some field crossings — watch for livestock as you go.
Millennium Coastal Park / Sandy Water Park, Llanelli
In Llanelli (Discover Carmarthenshire’s own page), the Sandy Water Park loop is a level, traffic-free route under 2km around a former steelworks cooling lake, step-free and buggy-friendly. A longer option continues through the Mabinogion Woods sculpture trail to the North Dock nature reserve. We couldn’t find a stated dog policy for this specific site, so treat it as subject to general council park rules rather than assuming it’s off-lead.
What we left out
Two more sites came up in our research that we’re deliberately not including here. The Amman Valley River Walk, between Ammanford and Brynamman, briefly crosses into Neath Port Talbot before coming back into Carmarthenshire, so it doesn’t sit entirely inside the county. Llyn y Fan Fach, a glacial lake on the Black Mountain, is genuinely in Carmarthenshire, but it’s a serious 10-mile hike mostly known as a wild-swimming spot rather than a casual dog walk, so we’ve left it for a different kind of guide.
Rural paths mean livestock, so a well-fitted harness and lead you trust matter more here than in a city park.
Frequently Asked Questions
Can dogs go off lead at Dinefwr Park?
No — dogs must be kept on a lead at all times across the parkland, and only assistance dogs are allowed in the Deer Park and on the boardwalk, because of grazing cattle and deer.
Are Brechfa Forest’s trails currently open?
At the time we checked, Natural Resources Wales’ own page stated the walking trails were closed, so check current status with NRW directly before you travel.
Written by Georgiana & Figo.
