As the flood tide enters the narrow area between the two islands it speeds up to 8.5 knots (16 km/h) and meets a variety of seabed features, including a deep hole and a rising pinnacle.

The Corryvreckan is the third largest whirlpool in the world,[1] and is on the northern side of the gulf, surrounding a pyramid-shaped basalt pinnacle that rises from depths of 70 to 29 m (230 to 95 ft) at its rounded top.

Flood tides and outflow to the Firth of Lorne in the west can drive the waters of Corryvreckan to waves of more than 30 ft (9 m), and the roar of the resulting maelstrom can be heard 10 mi (16 km) away.

[2] The Admiralty's West Coast of Scotland Pilot guide to inshore waters calls it "very violent and dangerous" and says "no vessel should then attempt this passage without local knowledge".

As winter approaches, she uses the gulf as her washtub, and it is said the roar of the coming tempest can be heard from as far away as twenty miles (thirty kilometres), lasting for a period of three days.

The story states that this MacPhail was carried off by a mermaid and they lived together in a grotto beneath the sea where they had five children, but eventually he tired of her and escaped to land.

In Adomnan of Iona's Life of St Columba, the saint supposedly has miraculous knowledge of a particular bishop who ran into the "whirlpool of Corryvreckan".

"In 1549, Dean Monro wrote of "Skarbay" that between it and "Duray": "ther runnes ane streame, above the power of all sailing and rowing, with infinit dangers, callit Corybrekan.

In the late 1940s, writer George Orwell and his three-year-old son (who lived at Barnhill in northern Jura) were briefly shipwrecked on the skerry of Eilean Mòr (south of the whirlpool) when boating in the gulf.

[15][16] Seeking to focus his main energies on completing a novel destined to become the dystopian classic Nineteen Eighty-Four, Orwell had fled the distractions of London in April 1947 and taken up temporary residence on the island of Jura in the Inner Hebrides.

When the boat's small engine suddenly sheared off from its mounts and dropped into the sea, Orwell's party resorted to oars and was saved from drowning only when the whirlpool began to recede, and the group managed to paddle the distressed craft to a rocky outcrop about a mile (2 km) distant from the Jura coastline.

The boat capsized as the group tried to disembark, leaving Orwell, his two companions, and his three-year-old son stranded on the uninhabited outcrop with no supplies or means of escape.