The rail industry is looking for ways to go faster and get safer. Logic suggests you reduce the train's centre of gravity and increase its wheelbase. This is precisely what Brunel did on the Great Western route connecting London and Bristol.
Brunel's 7ft (2.14m) broad gauge track allowed speeds of 100km/h and more compared with 55km/h achieved on the 5ft 8 1/2in (1.77m) standard gauge used in the rest of the country. Broad gauge track allowed trains to take corners faster. Broad gauge locomotives had better traction, were more efficient and did less damage to the rails than their standard gauge counterparts.
However, broad gauge required an additional 6% of land take over standard, pushing up engineering costs. Break points between broad and standard gauge line became a major aggravation as traffic grew.
Commercial pressure forced the Great Western Railway to convert its network to standard gauge by the 1890s.
But Brunel's engineering enterprise means that today, substantially less engineering work is required to accommodate highspeed and wide-bodied freight trains on former GWR broad gauge routes than in the rest of the country.