The quality of early turnpike roads was varied [REF].
The engineering work of Telford on the Holyhead Road (now the A5) in the 1820s reduced the journey time of the London mail coach from 45 hours to just 27 hours, and the best mail coach speeds rose from 5-6 mph (8-10 km/h) to 9-10 mph (14-16 km/h).