These historical maps are the work of the late Dr. Mike Stevens
The biggest rivers of England and Wales, the Thames, Trent and Severn have been used for navigation from before recorded history, as have been some others such as the Lee (or Lea) which was from early time an important route for bringing farm produce (grain in particular) into London. Some medieval river navigations were already disused by the date of this map, although several were later to be revived.
The earliest canals in Britain go back to Roman times. There can be no doubt about the Fossdyke, built by the Romans to connect the Rivers Witham & Trent. The Car (or Caer) Dyke was also Roman, but scholars do not agree whether it was built for navigation or for drainage. The lodes off the River Cam may or may not have been built by the Romans, but were clearly designed primarily for drainage. It is conjectural how early their secondary use for navigation began.
Various short, and short-lived, navigations had been built in the Middle Ages for specific purposes, several for bringing stone for building cathedrals. The cut to Glastonbury (which has been dated from the 10th Century), may well be one of these.
The Exeter Canal stands out as the first major non-Roman navigation in Britain. It was built in 1563 to bypass the river Exe, much obstructed by weirs, and so bring sea-going ships to Exeter. It had the first pound lock in Britain, the next being on the River Lee in 1577.
The Middle Level waterways and the Witham Navigable Drains were built for drainage, to make the fens into an area that could be farmed. The various river channels here were used for navigation in the middle ages, and an early venture into land drainage was undertaken by Bishop Morton, Bishop of Ely and Henry VII's Chancellor. The main work on the Middle Level was done by Cornelius Vermuyden between 1625 and 1651.
The main thrust of improving rivers for navigation began in Tudor times, and went into a period of renewed activity in the first half of the eighteenth century, seen on this map.