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North east Scotland is to be the focus of a historic alignment of three norths used for navigation in Great Britain, according to Ordnance Survey (OS).

Map experts said true, magnetic and grid north met at a single point for the first time in British mapping history at Langton Matravers, near Swanage in Dorset on Wednesday.

After August 2025, the triple alignment will not hit land again until around May 2026 near Newburgh on the east Aberdeenshire coast.

OS said its "last stop" on the UK landmass would be Fraserburgh around July 2026.

Due to the unpredictability of the magnetic field, OS said it was hard to forecast when the three norths might align again. It said an estimated would be a few hundred years at least.

Grid north is the blue line on an OS map that points to the North Pole.

True north is the direction of lines of longitude that also converge at the North Pole, but this varies from grid north as it reflects the curve of the Earth.

Magnetic north marks the north-ward line to the magnetic North Pole.

OS said the position of the magnetic North Pole moves continually north-westward due to adjustments in the magnetic field in the core of the Earth.

It said it was this "wandering" which had created the convergence and the historic alignment.

British Geological Survey data is among the information OS has used to help make its calculations.

In 2014, Mountaineering Scotland looked into the implications for navigation in the hills due to the shifting of magnetic north.