Alternative Names: None
Type of Dive: This is a lovely shallow shore dive, with a maximum depth of 8m at the end of the pier on high tides, but is usually round about 5m. The wooden pier is built at the end of a stone breakwater and is about 70m long. It has an absolute wealth of wildlife, particularly during the summer months and usually enjoys reasonable vis, but is worth a dive even when the vis is poor (usually because of south westerly winds) especially if you are prepared to look for small stuff. There are always edible crabs, plenty of purple swimming crabs, the occasional huge spider crab, shrimps, squat lobster, and plenty of fish life. The nesting ballan wrasse are very brave and will defend their nests by nibbling your fingers if you’re not too threatening and if you look closely in the weed towards the end of the pier, you can usually find two species of pipe fish. I have also occasionally seen octopus here, but they are usually very well hidden at the base of the pier legs. There are also plenty of sea-scorpions, and the odd dogfish or two (quite often caught on old angling hooks, so go armed with a small pair of pliers!), tompot blennies and, along the breakwater, millions of small gobies. Because of the abundant wildlife, anglers flock here, so stay under the pier at all times and enjoy the schools of sand eels, the occasional Pollock and the flat fish from a distance! Trefor Pier is a photographers heaven when the vis is good, particularly if you enjoy some macro photography, the pier supports and the rocky floor under the pier are covered with dead men’s fingers, plumose anemones, snake locks anemones, all manner of small crustaceans and shallow enough to be covered with dozens of different kelp varieties and the light that filters through, particularly on sunny days, is lovely.
It is also one of the best night dive sites I have dived, very easy to navigate using the pier legs, I have seen little cuttles here on more than one occasion and if you feel like turning your torch off for a moment, you can treat yourself to a mini firework display, bioluminescence turning startled sand eels into tiny comets. If you’re very, very lucky, you may see rays laying egg cases (mermaids purses), if you’re not that fortunate, should you find an egg case and gently shine your torch through it, you may see a wriggling embryo inside it.
Suggested Experience: This is a lovely dive site for all divers, from complete novices, to photographers and divers who enjoy wildlife.
Travel directions: From Caernarfon, drive along the A499, signposted Pwllheli, for about ten miles, shortly after driving through Clynnog Fawr the village of Trefor is signposted. Turn right and as you approach a small green (with a big glass bus stop) follow the signs on the right for Traeth (Beach), follow the narrow road between the houses to the beach at the bottom of the hill. It is a narrow road, so be prepared to move over for cars coming up the hill!
Parking directions: Parking is not usually allowed on the breakwater, unless it’s very quiet (the warden will sometimes let you get away with it) but you can unload the dive kit and park the car in the nearby car park, where there are also toilets and an emergency telephone. Google
Lat & Long: N53.000284 W-4.422212
Tides: Tide Tables
Site entry/exit: Kit up on the breakwater, by the picnic tables, unless you’re diving on low tide the steps here lead straight into the water (If you are diving on low tide, you’ll have to walk out along the bottom of the breakwater wall and put your fins on when you get to water!) Most people surface swim along the wall and submerge when reaching the pier. If you do decide to submerge, be aware that there is some small boat traffic, so you MUST stay next to the wall. Gwynedd council have erected a sign stating that dive flags and a surface marker buoy should be used, but this is impractical (read impossible??!) under the pier and I have never seen one used.
Underwater directions: Swim along under the pier to your hearts content, just use the pier legs as a guide! I usually swim out along the pier legs on the right, (make sure you look under absolutely everything!) mooch around at the end of the pier, there are some big wooden remains of an older pier where you may well find a lobby or two! And then swim back up the left hand legs. It’s really, really, REALLY hard to get lost!
Air & Nitrox fills: You don’t really need nitrox fills for this! In fact you hardly need air! You can get air fills from Vivian Dive Centre in Llanberis. (Or if you’re really nice to me I’ve got a compressor………..)
Site Hazards: The only real site hazards are the fishermen and the discarded fishing line. Stay under the pier at all times and take a knife or shears.
Nearest Public phone: In the car park.
Mobile Network service: I get good vodaphone coverage.
Pub: The nearest decent pub for me would be the Newborough Arms in Bontnewydd, on the way back to Caernarfon, good food at a decent price, but there are plenty all along the Pwllheli road.
Created by: Leigh.
U/Water Photos: Bill Seddon and Paul Smith
Dive site map:
Dive Report: Contact me