Geograph - photograph every grid square

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

Isambard Kingdom Brunel FRS (9 April 1806 – 15 September 1859), was a mechanical and civil engineer who is considered "one of the most ingenious and prolific figures in engineering history", "one of the 19th century engineering giants", and "one of the greatest figures of the Industrial Revolution, He changed the face of the English landscape with his groundbreaking designs and ingenious constructions". Brunel built dockyards, the Great Western Railway, a series of steamships including the first propeller-driven transatlantic steamship, and numerous important bridges and tunnels. His designs revolutionised public transport and modern engineering.
During his career, Brunel achieved many engineering firsts, including assisting in the building of the first tunnel under a navigable river and development of SS Great Britain, the first propeller-driven, ocean-going, iron ship, which, when built in 1843, was the largest ship ever built.
Brunel astonished Britain by proposing to extend the Great Western Railway westward to North America by building steam-powered, iron-hulled ships. He designed and built three ships that revolutionised naval engineering: the SS Great Western (1838), the SS Great Britain (1843), and the SS Great Eastern (1859).