The first plans for a canal between Hereford and Gloucester were made by Robert Whitworth, one of James Brindley's pupils, in 1777.

A branch would be built to Newent where there were minor coalfields, and the canal would be suitable for boats 70 by 8 feet (21.3 by 2.4 m), capable of carrying 35 tons.

[2] Hugh Henshall, who was the brother-in-law of James Brindley, was asked to re-survey the route in 1792, and recommended a diversion to Newent.

[4] In order to build the tunnel, twenty shafts were sunk along its route, so that there could be multiple working faces.

[10] A feeder from the River Frome to the summit level was completed in August 1842,[11] and the canal opened in stages as it was completed, with extensions to Canon Frome wharf in January 1843, Whithington wharf in February 1844, and finally to Hereford basin on 22 May 1845.

[14] This was not always successful, as the Hereford Times carried articles in May 1851 about an incident in which boats travelling in opposite directions had met in the middle, and neither would give way.

[15] In 1858, the canal carried 47,560 tons of goods, and generated an income of £7,061 in 1860, but some of this was derived from the carriage of materials to build railways in the area.

[17] This did not take place immediately, but on 30 June 1881, half of the canal was closed, and sections of it were used for the course of the Ledbury and Gloucester Railway.

A meeting was held in Hereford to facilitate this on 13 April 1983, at which a canal society was formed, which soon became actively engaged in restoration.

[27] In late 2011, the Trust were able to buy a short section of the former canal route adjacent to the basin site (Vineyard Hill).

[30] Major re-development in Hereford city centre has resulted in the provision for a new canal bed which it is hoped will eventually link to a new terminal basin.

[24] The canal connects to an un-navigable part of the River Severn, separated from the main channel by weirs at Maisemore and Llanthony, both of which have derelict locks associated with them.

The Canal Trust used a legacy to purchase the site, which includes two cottages, some land, and a small section of the River Severn as well as Llanthony lock.

[32] Over Lock is around 30 feet (9.1 m) deep, as it has to cope with the large tidal range of the River Severn, and so restoration would be difficult.

In early 2022 the Trust asked a consulting engineer from the Inland Waterways Association's Restoration Hub to assess how the canal could be connected to the river.

[34] When the railway replaced the canal, they constructed a high level bridge over the road, which was lowered to accommodate this solution.

[36] In November 2021, planning permission was granted to allow the Trust to construct 660 yards (600 m) of new canal at Malswick, on the section that was converted into a railway.

[33] The Wharf House at Over Basin is a restored lock cottage that, until 2019, served as a visitor centre and restaurant.

In 2019, management of the Wharf House was transferred to a private firm, and the restaurant was renamed The Lock Keepers.