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A group of 15 - 20 islands (depending on the tides) offshore of Seahouses, Northumberland. They are the most easterly outcrops of the Whin Sill (a dolerite intrusion across north east England). The islands are divided into the inner and outer islands. The Islands are an important breeding ground for many seabirds having a large Puffin population. There is also an important seal colony here. The whole area is designated a National Nature Reserve.
Wikipedia: Link

The Great Whin Sill is a large igneous intrusion into the rocks of Northern England. The intrusion is dated at 295 million years ago; the rock is dolerite. Several classic locations of Northern England owe their location to this sill : Hadrian's Wall, Farne Islands, Holy Island, Bamburgh Castle.

Listed buildings and structures are officially designated as being of special architectural, historical or cultural significance. There are over half a million listed structures in the United Kingdom, covered by around 375,000 listings.
Listed status is more commonly associated with buildings or groups of buildings, however it can cover many other structures, including bridges, headstones, steps, ponds, monuments, walls, phone boxes, wrecks, parks, and heritage sites, and in more recent times a road crossing (Abbey Road) and graffiti art (Banksy 'Spy-booth') have been included.

In England and Wales there are three main listing designations;
Grade I (2.5%) - exceptional interest, sometimes considered to be internationally important.
Grade II* (5.5%) - particularly important buildings of more than special interest.
Grade II (92%) - nationally important and of special interest.

There are also locally listed structures (at the discretion of local authorities) using A, B and C designations.

In Scotland three classifications are also used but the criteria are different. There are around 47,500 Listed buildings.
Category A (8%)- generally equivalent to Grade I and II* in England and Wales
Category B (51%)- this appears generally to cover the ground of Grade II, recognising national importance.
Category C (41%)- buildings of local importance, probably with some overlap with English Grade II.

In Northern Ireland the criteria are similar to Scotland, but the classifications are:
Grade A (2.3%)
Grade B+ (4.7%)
Grade B (93%)

Read more at Wikipedia Link

Classically, beacons were fires lit at well-known locations on hills or high places, used either as lighthouses for navigation at sea, or for signalling over land that enemy troops were approaching, in order to alert defences. As signals, beacons are an ancient form of optical telegraphy, and were part of a relay. Many hills in the UK are called Beacon.