The Menai Strait
Photo : Tim Snow

The Menai Strait

The Isle of Anglesey is separated from the Welsh mainland by the Menai Strait (Welsh: Afon Menai) which runs in a roughly North East – South West direction and is about 18.5miles (29.8km) in length

The south western approach of the Menai Strait starts at Aber Menai point on the Anglesey shores, which is opposite Fort Belan. The northern eastern end of the Strait start at Puffin Island and stretches across towards Penmaenmawr, this is the widest part.

Many business’s now rely on the Menai Strait for their income.


Aber Menai Point

Ex bombs loaded, Fort Belan


The Royal town of Caernarfon, where Prince Charles was invested at Caernarfon castle is the first town along the Menai Strait.

Along this stretch of the strait you have along sandbank running through the middle.

Y Felinheli (Port Dinorwic)

The coastal village of Port Dinorwic was once used to ship Welsh slate all around the world like it’s sister port, Port Penrhyn.

The stately home Plas Newydd

Plas Newydd

On the Anglesey side of the Menai Strait after Y Felinheli you will see Plas Newydd the stately ancestral home of the Paget family, now in the care of the National Trust.

This beautiful 16th century home looks straight out onto the Menai Strait, with views up to Port Dinorwic and down to the Britannia bridge.

Plas Newydd is unique as it now uses the sea water from the Menai Strait to heat a 300 year old mansion using a special 300kW marine source heat pump. The special pump which cost £600,000 to install and is the first of it’s size to be installed in the UK.

Fishing by the Britannia Bridge on Anglesey

The Britannia Bridge

The Britannia Bridge was the second bridge to be built to take traffic across the Menai Strait. Built by railway and civil engineer Robert Stephenson.

The original tubular bridge caught fire and the tubes that the trains travelled through were subsequently had to be removed.

With the increase in traffic and the construction of the A55 dual carriageway the road deck was built over the railway line crossing the Britannia bridge.

Looking across the Menai Strait towards the Menai Suspension bridge

The Swellies (Pwll Ceris)

The Swillies or Swellies as it is sometimes known is the body of water that runs between the Britannia Bridge and the Menai Suspension bridge.

This beautiful area of water can be extremely dangerous and fast flowing at big tides.

The section of the Anglesey Coastal Path that travels along this section of the Menai Strait is particularly beautiful, with close up views of the island in the middle, Ynys Gorad Goch.

Ynys Gorad Goch in the middle of the Menai Strait

Ynys Gorad Goch

Ynys Gorad Goch or Red Weir Island is situated in the Swellies and nearer to the Britannia bridge.

The Island was once used to trap fish and then smoke them. During the 1820’s a trap was built on the Island to catch fish during high tide.

Then as the tide went out the fish were recovered. The fish trap on the island is still visible today.

The Menai Suspension Bridge from the air

The Menai Suspension Bridge

The Menai Suspension bridge was the first of the two bridges to be built. Started in 1818 and finished in 1826 by Scottish engineer Thomas Telford.

Originally a toll bridge, but freed from toll on 31 December 1940. Built from local limestone sourced from the Penmon quarries at the eastern end of the Menai Strait.

Prince’s Pier

Much of the area around and including Prince’s Pier belonged to the wealthy Davies family, who developed a large timber merchant business, mainly importing timber and exporting slate to North America. Their warehouses and timber yard were constructed in 1827 and the Prince’s Pier Wharf in 1832.

In more recent times Menter Mon purchased Prince’s Pier and buildings to be developed in conjunction with Menai Heritage. In the spring of 2014 the first phase was completed when the building was fully refurbished and the adjacent pier masters house was converted into offices.

The next phase is to raise funds and build an exhibition space with cafe so that the history of the Menai Strait, its bridges and their history can be shared from this location to visitors of Anglesey and the local community.

RV Prince Madog stops of at St. Georges Pier in Menai Bridge

St. George’s Pier

St. George’s pier in Menai Bridge, although now totally modernised is one of the original piers on the Menai Strait where passenger ships would arrive in the mid 1800’s and early 1900’s bringing passengers to the local area.

Pleasure steamers from the Liverpool and North Wales Steamship company would stop of here, Garth pier and at Beaumaris pier.

Today the pier is frequently used by the nearby RibRide boat tours company and is a permanent home for the School of Ocean Science research vessel RV Prince Madog.

School of Ocean Sciences

Since the early 1950’s Bangor university’s School of Ocean Sciences has been based in Menai Bridge. Situated on the shores of the Menai Strait, this is one of the largest university Marine Science departments in Europe.

The strait provides an interesting and relatively sheltered stretch of water between the harbours of Conwy at the north-east end and Caernarfon to the south-west.