His father Marc Isambard (1769-1849) was born near Rouen but he was an outspoken critic of the French Revolution and was forced to flee Paris in 1793, escaping to America. Marc made his name as an architect and engineer in New York before moving to England in 1799.In 1803 he devised a system for mass producing pulley blocks for the Royal Navy, but when his Battersea sawmill was destroyed by fire in 1814, his fortunes went into a decline. He was bankrupted im 1821 and thrown into prison, but the Government bailed him out with a grant of £5,000.
Three years earlier, Marc had invented a tunnelling shield, which he used to dig the Rotherhithe Tunnel under the River Thames. The project began in 1825 and took eighteen years.Isambard Kingdom Brunel - 'Kingdom' was his English mother's maiden name - was to be more famous than his father. He was born in Portsmouth, and after spending two years at the College Henri Quatre in Paris, he joined his father's office in 1823.
There, he helped with the design of the Thames tunnel before planning the Clifton Suspension Bridge at Bristol.
This was completed more than 30 years later, using chains taken from Brunel's own Hungerford Bridge over the Thames but, meanwhile, Brunel's name had become forever associated with the Great Western Railway.
He surveyed and built (1833-1841) the Great Western track from London to Bristol and, believing that Stephenson's 1.44-metre gauge - the distance between the rails - was too narrow, he opted to use a broader, six-foot gauge for his line.
In the end, this decision was to prove expensive because everyone else adopted the Stephenson standard and the Great Western were eventually forced to fall into line, scrapping their wider engines and rolling stock and re-laying their lines later in the century.
The Great Western line to Bristol was part of Isambard Kingdom Brunel's grand vision - a link between London and New York - and he also built the ships for the sea link. The first trans-Atlantic steam service was provided by the Great Western, at 236-feet long the biggest liner afloat by some margin when she made her maiden crossing in 1838.
The Great Britain (1845, now preserved at Bristol) was the first propellor-driven iron steamship, and she could carry 250 passengers and more than a thousand tons of cargo while the Great Eastern, launched at Millwall in 1858 and many years ahead of her time, was not a commercial success, but was nevertheless used to lay the first Transatlantic cable.
The Great Eastern could carry 4,000 passengers or up to 10,000 troops, and besides her steam engines, she could cram on more than 5,000 square metres of sail. Brunel was taken ill while watching the Great Eastern undertake her sea trials, and died on September 15th, 1859.
Among his other major achievements were the docks at Bristol, Cardiff and Milford Haven, and one of his more memorable works was the unusual cantilever bridge that carried the Great Western Railway over the River Tamar into Cornwall. He was already ailing when the bridge was finished, and was wheeled out on a rail trolley for the opening ceremony.