Part of Canada
- Where
- New Brunswick & Nova Scotia,
Atlantic Canada - Coordinates
- 45.25° N
64.75° W - Biome
- Macrotidal bay, mudflats
& sandstone coast - The tides
- Recorded extreme 16.3 m
at Burntcoat Head - Water moved
- c. 160 billion tonnes
per tide - Best visited
- May–October
The sea here leaves twice a day — all of it, in a hurry — and comes back the same way. I walked on the floor of the ocean before lunch and paddled over my own footprints after tea. The rule is simple: be elsewhere when the sea returns. I wrote it down twice.
The short answer
The Bay of Fundy, between New Brunswick and Nova Scotia in Atlantic Canada, has the highest tides on Earth. The recorded extreme, at Burntcoat Head in the Minas Basin, is 16.3 metres between low and high water — the height of a multi-storey building — and the working range in the upper bay runs around 14 metres. Each tide moves roughly 160 billion tonnes of seawater in and out, commonly described as exceeding the combined flow of the world's rivers over the same hours.
Why it's worth knowing
The mechanism is resonance. The bay is a long, narrowing funnel whose natural sloshing period nearly matches the rhythm of the ocean tide itself, so each incoming tide arrives in step with the water already rocking up the bay, and the ranges amplify toward the head — modest at the mouth, enormous in the Minas Basin.
What that means on the ground is the point. At low tide, the upper bay's floor is exposed for kilometres — red mudflats, sculpted sandstone, tide pools — and you can walk on it. Six hours later the same ground lies under a serious depth of ocean. The safety rule is absolute and locally enforced with signage and common sense: know the tide times, and be off the flats well before the water returns.
The field notes
Flowerpots and a floor you can walk on
At Hopewell Rocks in New Brunswick, tidal erosion has carved sandstone stacks — the flowerpots — topped with trees. At low tide you walk among their bases on the sea floor; at high tide, kayaks weave between their crowns. Same rocks, same day, two different worlds.
At Burntcoat Head in Nova Scotia, keeper of the record, a path leads down onto the floor of the Minas Basin itself — the single best place on the planet to stand where the tide's range is greatest.
The wave that runs uphill
Where the returning tide squeezes into the rivers at the bay's head, it can arrive as a tidal bore — a wave running upstream against the current. On the Shubenacadie in Nova Scotia, rafting operators ride the bore and the churning standing waves behind it, one of the odder adrenaline sports anywhere: whitewater created twice daily by the moon.
A coastline with receipts
The bay's cliffs keep records. At Joggins in Nova Scotia, a UNESCO World Heritage fossil coast, the tides continually re-cut cliffs holding roughly 300-million-year-old coal-age forests and some of the earliest known reptiles — fossils examined where they lie, not collected. And on the mudflats each late summer, semipalmated sandpipers in the hundreds of thousands fatten on mud shrimp before a nonstop ocean flight toward South America, one of the hemisphere's great migration spectacles.
- Walk the ocean floor at low tide, tipping my hat to the flowerpots.
- Be back up the stairs long before the sea's return. (Underlined. Twice.)
- Watch the bore arrive up the river like a rumour becoming fact.
- Admire the fossils in the cliffs and leave every one of them employed exactly where it is.
- Paddle at high tide over the morning's footprints.
Standing on the ocean floor. At Burntcoat Head or Hopewell Rocks at low tide, the thing underfoot — rippled red mud, barnacled rock, the sea's own furniture — will be under many metres of Atlantic before dinner. No fence, no glass: just a floor that becomes a ceiling twice a day.
Tally, in the marginThe only floor I know that becomes a ceiling twice a day — punctual, dramatic, and entirely indifferent to hats.
Getting there
The bay is road-trip country. From Halifax, the Nova Scotia shore — Burntcoat Head, the Shubenacadie bore, the Joggins cliffs — makes a natural two-to-three-day loop; from Moncton or Saint John, the New Brunswick side pairs Hopewell Rocks with Fundy National Park's coastal trails. The two shores are complementary rather than duplicate, and ambitious itineraries do both.
Everything worth doing is timed to the tide, so the tide table is the real itinerary: plan each stop for the right water, and hold the iron rule of being off the flats comfortably before the turn — local guidance says two hours. The season runs May to October; late summer adds the sandpiper flocks, and Brier Island's whale boats at the bay's mouth round out a week.
Common questions
Where are the highest tides in the world?
The Bay of Fundy, between New Brunswick and Nova Scotia in Canada, has the highest tides on Earth. The recorded extreme at Burntcoat Head in the Minas Basin is 16.3 metres between low and high water, with typical upper-bay ranges around 14 metres.
Why are the Bay of Fundy tides so high?
Resonance. The bay is a narrowing funnel whose natural oscillation period nearly matches the roughly twelve-and-a-half-hour rhythm of the ocean tide, so each tide arrives in step with water already sloshing up the bay and the range amplifies toward the head, reaching its extreme in the Minas Basin.
Can you walk on the ocean floor at the Bay of Fundy?
Yes. At low tide, sites such as Burntcoat Head Park and Hopewell Rocks open kilometres of exposed sea floor to walkers - red mudflats, sandstone stacks and tide pools. The absolute rule is to know the tide times and be off the flats well before the water returns; local guidance says two hours.
What are the Hopewell Rocks?
The Hopewell Rocks are sandstone sea stacks in New Brunswick, carved by tidal erosion into tree-topped 'flowerpots'. At low tide visitors walk among their bases on the exposed sea floor; at high tide, kayaks paddle around their crowns - the same rocks, transformed twice daily.
What is tidal bore rafting?
On rivers at the bay's head, the returning tide can arrive as a bore - a wave running upstream. On Nova Scotia's Shubenacadie River, operators run rafts on the bore and the standing waves behind it: whitewater generated twice a day by the tide itself.
What are the Joggins Fossil Cliffs?
The Joggins Fossil Cliffs on Nova Scotia's Fundy shore are a UNESCO World Heritage site whose tide-cut cliffs expose roughly 300-million-year-old coal-age forests and some of the earliest known reptiles. The tides continually reveal new material, which is examined in place rather than collected.