‘Three norths’ set to leave England
A once-in-a-lifetime event in Berwick-upon-Tweed
Press Office
What are the ‘three norths’?
‘True north’ is the direction to the geographic north pole.
‘Grid north’ is where the vertical blue lines shown on Ordnance Survey (OS) maps converge.
‘Magnetic north’ is the direction that a compass needle points, as it aligns with the Earth’s magnetic field.
In November 2022, geospatial history was made as all three ‘norths’ aligned, and met at a point in Langton Matravers in Dorset. Below is a video that we made at the time:
Now, three years later, new magnetic field data collected by the British Geological Survey (BGS), and calculations made by OS have shown that the triple alignment is set to leave England. It will depart at Berwick-upon-Tweed on 13 December 2025, and move into the North Sea.
Further predictions suggest that the triple alignment will hit land again at the end of October 2026 in Drums, just south of Newburgh in Scotland. After passing through Mintlaw, its last stop in Scotland will be Fraserburgh around mid-December 2026, before it returns to the North Sea.
A once-in-a-lifetime event
Once over the North Sea, the three norths are expected to continue northwards before leaving the British national grid. They will also stay in alignment for another couple of years, before magnetic north separates from true north and grid north.
Given that magnetic north moves so slowly, it will probably take several hundred years for this triple alignment to ever visit again. For example: the triple alignment began back in 2014, when magnetic north became east of grid north for some locations in Great Britain – a circumstance that hadn’t been recorded in Britain since the 1660s!
This event affected navigators using a compass, who needed to adjust their bearing by subtracting instead of adding the difference between magnetic and grid north.
The ‘three norths’ journey
During the three norths’ time in England, they moved northwards through Poole near the end of 2022, then through Chippenham and Birmingham before reaching Hebden Bridge, West Yorkshire, in October 2024.
The triple alignment then passed though the Pennines, and will leave England at Berwick-upon-Tweed.
Mark Greaves, Earth measurement expert at OS, said:
“Due to refinement of the underlying models and the prediction data, the alignment’s progress has slowed slightly since the initial predictions back in 2022. When it crosses the coast at Berwick-upon-Tweed it will have travelled 576km (about 358 miles) in 1127 days so that’s about 511m per day (or about 5.9 mm per second or about 0.013 miles per hour). It will likely be a very long time before the alignment comes around again.”
"The three norths combining in Great Britain has been a once-in-a-lifetime occurrence. Although part of geospatial history, there is no impact for navigators, pilots and captains once the alignment leaves, and people will still need to continue to take account of the variation between magnetic north from a compass and grid (or true) north on a map. It’s been a privilege to be able to observe this phenomenon over the past few years. The magnetic field is not predictable in the long term, so we don’t know how many hundreds of years it will take for this historic alignment to occur again."
OS and the BGS Geomagnetism team collect detailed measurements of the magnetic field at more than 40 sites around the UK. These enable scientists to create high-resolution maps and make accurate forecasts of the changing declination angle.
Several factors, including changes in the flow of the Earth’s liquid outer core, the iron content of the local rocks and the variations in the magnetic field that are caused by the Sun, mean these predictions have some uncertainty and are a rough estimation of when the three norths are due to leave British soil.
BGS and OS will continue to work together, with plans to review predictions in June 2026 before the final departure in Scotland.
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