# Coastline of the United Kingdom

For the problem in fractal geometry, see How Long Is the Coast of Britain?.
Bedruthan Steps, North Cornwall, A spectacular section of the UK coastline, managed by the National Trust.

The coastline of the United Kingdom is more broken and has a fractal or Hausdorff dimension or 'wiggliness' of 1.25, which is higher than many other coastlines (Australian coastline has a fractal dimension of 1.13, and that of South Africa is very smooth at D = 1.02)[1]of similar sized countries;[2] it is accessible and very varied in geography and habitats.

The mapping authority for the United Kingdom, the Ordnance Survey, records the coastline of the main island, Great Britain, as 11,072.76 miles rounding to 11,073 miles (17,820 km). If the larger islands are added the coastline, as measured by the standard method at Mean High Water Mark, rises to about 19,491 miles (31,368 km).

The British Cartographic Society [1] points out that "The true answer is: it depends!". The length arrived at depends on the scale at which you measure it. It is a meaningless statistic without knowing the scale of the map being used and the accuracy of the measurement. The smaller (closer) the scale, the larger the answer. For example, according to the CIA Factbook, the length of the UK coastline is around 12,429 km[3] or 7723 miles. Unfortunately the CIA Factbook figures provide no detail is provided as to how this was calculated.

And because the resultant coastline length increases exponentially faster than the increase of scale of measurement, there is no such thing as 'an approximate answer" to this question.

Note that the measurement of any coastline is subject to variation depending upon the scale of map used and is an approximation. The smaller the map scale and the smaller the ruler will result in more detail being revealed and thus a greater length. This is referred to as the coastline paradox. A coastline is also fractal-like — which means that it has self-similar properties, similar at every scale — the closer the observer looks, the more detail is revealed, leading to a greater overall length.)[citation needed]

Nowhere in the UK is more than 113 kilometres (70 mi) from the coast. It is estimated that around 3 million people (out of 60 million) live on the coast of the UK. The places furthest from the coast are Coton in the Elms in Derbyshire, which is equidistant from Fosdyke Wash in Lincolnshire; White Sands between Neston in Cheshire and Flint, Flintshire in Wales; and Westbury-on-Severn Gloucestershire.[4][5]

The geography of the UK coastline consists of a variety of natural features. These consist of islands, bays, headlands and peninsulas. Of the 1,000+ islands within the UK, only 290 are permanently inhabited. Of the remaining islands, some are used for farming and are occupied occasionally, some are nature reserves with restricted access and some are little more than sea-swept rocks. The main occupied islands and island groups in the UK are as follows.

(Note that the Channel Islands (including Jersey, Guernsey, Alderney and Sark) and the Isle of Man are not part of the UK. They are self-governing Crown dependencies. Their coastlines are not coastlines of the United Kingdom.)

Peninsulas around the UK coast include:

Bays, sea lochs, (loughs) and large estuaries include: