Anglesey · United Kingdom · Channel & pass
Menai Suspension Bridge
Dahlia anemones in their hundreds, reached on a short slack-water window
Photo: Monsyn · CC BY-SA 4.0
A slack-water shore dive in the Menai Strait at the Menai Suspension Bridge, where the current runs very hard and every dive has to be timed to the tide. Dahlia anemones cover the seabed in large numbers, crabs are everywhere and dogfish turn up; most dives reach 12–14 m, and 16–18 m is possible.
Also known as Menai Bridge Nature Trail.
Where it is and how deep
53.2216° N, 4.1646° WApproximate position — the dashed circle shows where the site lies; your operator's briefing has the mooring.
The dive
The entry is from the shore and relatively easy, but the timing is not. The current screams through the Strait, so the dive has to be fitted inside slack water, which lasts up to an hour on a good neap tide and only about 30 minutes on springs. The first thing to notice on the seabed is the number of dahlia anemones, with crabs on every side of them.
Telecommunications cables run right across the Strait, and the dive follows one out from the shore and back again. The usual turn point is 13–14 m after 25–30 minutes, because slack water here does not last long. Dogfish appear among the crabs and anemones. Depths of 16–18 m are possible but 12–14 m is more common, and visibility varies: one team had 3 m in the deeper sections.
Marine life and season
The sources we used don't single out particular species here.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Fair | Fair | Fair | Good | Good | Good | Good | Good | Good | Good | Fair | Fair |
Season follows Anglesey: April to October is the main diving season, when water temperature and visibility are best; local clubs keep diving through the winter months.
Know before you go
- The current runs very hard through the Strait; time the dive to slack water and turn after 25–30 minutes, before the tide starts to run again.
- Boat traffic uses the Strait, so ascents need care.
Photos from Menai Suspension Bridge
David Dixon · CC BY-SA 2.0
DS Pugh · CC BY-SA 2.0
Dive videos
Shore dive, menai bridge nature trail part 1 · HazelgroveSAC on YouTube
Sources
- Above 18m: Diving in the Menai Strait — Divernet
- Shore diving sites — Deifwyr Môn Divers
Photo credits
- A white suspension bridge spanning a tree-lined strait with rocks exposed at low water and mountains behind by Monsyn, CC BY-SA 4.0, via Wikimedia Commons
- Massive stone arches of a suspension bridge rising from the water beside the shore by David Dixon, CC BY-SA 2.0, via Wikimedia Commons
- A wooded headland and the turquoise water of a strait, with a distant bridge on the horizon by DS Pugh, CC BY-SA 2.0, via Wikimedia Commons
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