‘Three Norths’ one year on – where are they now?
Amid a blaze of media interest on 2 November 2022, map reading history was made in the quiet Dorset village of Langton Matravers. It was here that the three norths of navigation – True North, Grid North, and Magnetic North, were recorded as meeting up on British soil for the first time. Yet this quirk of navigational science hasn’t been the only time the three points have converged in the same place in the past year. Its path has passed through many different locations as the triple alignment has inched up the country.
So what exactly are the three norths and why does it matter?
True North is the direction of lines of longitude on maps which all curve up to meet at the geographic North Pole.
Grid North is the direction of the vertical blue grid lines on an Ordnance Survey map.The True North direction generally curves slightly away from the Grid North direction – except along one vertical grid line where they both agree. This vertical line is longitude 2 degrees west or National Grid eastings line 400000m. This line runs up the middle of the country, starting all the way down at Langton Matravers.
Magnetic North is the direction a compass needle points to. This shifts gradually over time because of the Earth’s fluctuating magnetic field.
For expert navigators this matters because when using a compass there is a difference between magnetic north and grid north. So the compass (magnetic north) doesn’t exactly correspond to the north (grid north) illustrated on the paper map.
The rarity of all three north’s aligning has occurred because of the following circumstances. Since the 1660s magnetic north was always to the west of grid north in Britain. But in 2014 that changed, and magnetic north now found itself moving to its east. By 2022 it coincided with true north’s longitude line to the North Pole, and lo and behold all three north’s coincided locations together.
As magnetic north continues to slowly move its position, by 2026 the triple alignment will move apart and is not expected to come together again in Britain for hundreds of years.
In the meantime, the fleeting location of this triple alignment is slowly moving up the country along the longitude 2 degrees west / 400000m eastings line.
Where are the three norths now?
Exactly one year on OS has re-calculated the triple alignments progress (using the latest magnetic data from the British Geological Survey )and Fladbury, a village on the banks of the River Avon in Worcestershire, is where the three norths currently coincide. Over the following months the triple alignment will pass through Birmingham, Hebden Bridge (October 2024), and the Pennines before leaving the English coast at Berwick-Upon-Tweed a year later in November 2025. It does not hit land again until around August 2026 at Drums, just south of Newburgh in Scotland. Once it passes through Mintlaw its last stop in Great Britain is Fraserburgh, around November 2026.
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