During the height of summer, 1st May to 30th September, many of the beaches in Pembrokeshire have dog restrictions in place.
In Tenby, your best option is the South Beach, the majority of which accepts dogs. For the detailed area map https://eyz9ntboeer.exactdn.com/wp-content/uploads/Tenby-South-beach-dog-restriction-map.pdf
On the North Beach side of Town, during the summer months, restrictions are in place in most parts. For a detailed map, https://eyz9ntboeer.exactdn.com/wp-content/uploads/Tenby-North-beach-and-promenades-dog-restriction-map.pdf
Guide dogs are welcome on Pembrokeshire’s beaches all year round.
There are notice boards on all of the dog restricted beaches above, with full details of the bylaws and maps of the restricted areas. During the summer months, there are signs out on the beach, which help you identify the start and end of a dog restriction area or you can ask one of the RNLI lifeguards patrolling the beaches. They’ll point you in the right direction.