Simple Tides / Guides / Highest Tides in the World

The Highest Tides in the World (and Why the Bay of Fundy Wins)

Most coastlines see a tidal range of a few feet. A handful of places, thanks to a specific combination of geography and physics, see forty feet or more between low and high tide in a single cycle.

Bay of Fundy, Canada — the record holder

The Bay of Fundy, between Nova Scotia and New Brunswick, holds the record for the largest tidal range on Earth, with some locations seeing a difference of close to 50 feet (about 16 meters) between low and high tide. The bay's shape and depth happen to match the natural resonant period of the incoming tide almost exactly, which amplifies the swing far beyond what the open ocean produces nearby.

Other extreme tidal ranges

Ungava Bay, Canada — a genuine rival to Fundy, with ranges reported over 40 feet in parts of the bay.
Bristol Channel / Severn Estuary, England — one of the largest ranges in Europe, and home to the famous Severn tidal bore.
Gulf of Khambhat (Cambay), India — ranges reported up to roughly 36 feet, among the largest in Asia.
Cook Inlet / Turnagain Arm, Alaska — ranges up to around 40 feet, and another location with its own tidal bore.

Why these specific places

It comes down to funnel-shaped coastlines that narrow and shallow moving inland, combined with a natural resonance where the time it takes a wave to slosh from the mouth of the bay to its head and back roughly matches the tidal cycle itself. That resonance keeps reinforcing the incoming tide rather than letting it dissipate, the same underlying mechanism behind the world's biggest tidal bores.