SO rarely can any physical feature of the world in height, depth or breadth or strength be at its greatest in these islands.

We often forget the one feature which is almost unique – the tides of north west Europe which reach their peak on the Monmouthshire coast.

This is no ordinary physical feature, but a daily moving mass of water – moving backwards and forwards at the exactly the hour predicted for them over millions of years.

It is possible to predict the exact height to the nearest foot or 10th of a metre and the exact time to the minute of the arrival of the tide at Chepstow in 1,000 years’ time.

South Wales Argus:

Chepstow Bridge at high tide

Who knows what the world will look like then, but we do know exactly what time the tide will arrive at Chepstow on the morning of January 1, 3021 – as the saying goes ‘Time and tide waits for no man’.


It is awesome to think that the most prominent natural feature on earth of the two largest and brightest objects in the sky, the Earth and the Moon working together, is the daily rise and fall of the tide and that no other town on the planet sees this more dramatically than Chepstow.

It is an amazing feature.

The daily forces of the Moon and of the Sun on our plant are seen in the tides and they are at their most extreme in eastern Canada, the Severn Estuary and the coast of north west France.

The next highest tides in the world are in extremely remote locations - south east Argentina, north west Australia, Alaska and north east Russia.

South Wales Argus:

The River Wye in Chepstow on a day when the tide was particularly high

But by far the best location to observe the planet’s highest tides are on the Monmouthshire coast and Gloucestershire and Somerset.

The Severn Estuary has the second or third highest tides in the world.

The most northerly reaches of the bay of Fundy in eastern Canada and the south west part of Ungava Bay, 500 miles north of the Bay of Fundy, have slightly higher tidal ranges at their extremes than the Severn Estuary, but only by about two metres, which would look no different than the high water on the Monmouthshire coast.

In fact, the Monmouthshire coast tides would look higher because there are no vertical structures or bridges next to or over the bay of Fundy.

South Wales Argus:

Chepstow Bridge at low water

There is no Chepstow Bridge or Clevedon Pier against which the rise of 15m (48 ft) tide movement can be monitored.

Many towns and villages along the shores of the Bay of Fundy make much of the tides, but few of them actually experience the range that we take for granted every day.

Where the tide range for the Bay of Fundy is slightly higher than on the Monmouthshire coast, it is remote and sparsely populated.

In north west France, in the Baie de St Michel, the tide goes out a long way and comes back in a long way so it hard to see the full range, but by comparison the Severn Estuary is narrow and the Wye and Usk estuaries narrower still, so we see the full range of the tide and the full power of the Moon and the Sun raising the water level.

We have rivers at Chepstow and Newport which flow both north and south in the same day. How strange is that?

But we take it all as normal.

We should make more of this natural phenomenon, but it takes five hours to see the tide rise 40ft, so visitors need something else to do in the meantime.

South Wales Argus:

Mont St Michel, France

This is why Chepstow is such a good place to see the tides because there are pubs and eateries by the river, shops in the town, Chepstow Castle and museum to visit, and even a quick trip to Tintern Abbey, five miles away, to occupy time between high and low tide.

When we are allowed to due to the current restrictions there are a number of places along the riverbank where you can sit, enjoy a drink or a meal and watch the tide.

In fact, the closest bar to a tide more than 45ft (14m) anywhere in the world is probably the Riverside Wine Bar at The Back, Chepstow.

The Port pub at Port Williams, Nova Scotia, might be able to claim a few feet more on the tide but it’s a long way to go - and Chepstow has the better setting.

South Wales Argus:

The Bay of Fundy, Canada

The highest tides are almost always in the morning about 8am to 10am and the tides are at their lowest about 4pm to 5pm, rising again to high tide at 9pm to 10pm.

Choose any day in Chepstow from 9am to 5pm at any time of the year to see the high tide changing to low tide and the river flowing south to the sea and an evening in the summer from 5pm to 10pm would see the river flowing northwards at great pace for the evening high tide.

If you are lucky you may even catch the turn of the tide usually between 4.30pm and 6pm when the river stops flowing and falls silent for a few minutes and changes its direction of flow – a phenomenon which in any other part of the world would be the basis for a flourishing tourist industry.

Only storm surge tides like that of January 2014 for example or the famous storm surges of 1607, 1703, 1883 (commemorated on a plaque in Chepstow) and 1981, plus a few notable others, will exceed the height of the highest astronomical tides and nowhere else in the world will you be able to see these high tides as clearly and as closely as at Chepstow in Monmouthshire.