The Grand Union Canal is the longest canal in the UK spanning across several counties and linking the major cities of Birmingham and London.
A brief history of the Grand Union Canal
The Grand Union Canal started life as the Grand Junction Canal, built at the end of the 18th century, allowing the key towns and cities of the Midlands to send goods from the Birmingham navigation to the nation’s capital.
Gradually between 1894 and 1929 several independent waterways — the oldest being the navigations around the River Soar in Leicestershire, the longest the Grand Junction Canal from Braunston to the River Thames, were amalgamated into the Grand Union which includes a huge flight of locks.
The term ‘Grand Union’ is now generally taken to mean the canal from the Thames at Brentford to the junction with the Digbeth Branch in Birmingham to the Birmingham Canal; see our canal map below.
The canal network now is used predominantly for leisure activities such as boat hire, canal boat holidays, boat moorings as well as sports and activities such as canoeing and paddle boarding. There is also a Grand Union canal walk route alongside parts of the waterway.
Top Grand Union Facts
Leaving central Birmingham, the Grand Union heads south towards the popular towns of Warwick and Royal Leamington Spa.
Then on to Braunston and Stoke Bruerne, passing through the Blisworth Tunnel, and winding with narrow locks on to the Vale of Aylesbury after passing through the popular market towns of Leighton Buzzard and Tring.
Through the Chiltern Hills, the Grand Union Canal climbs through Berkhamsted, Apsley and Kings Langley on towards Watford. The canal passes under the M25, skirts to the west of Watford, avoiding the town centre, on to Rickmansworth.
From there it runs through the Colne Valley Regional Park, almost following the line of the M25, on through Uxbridge and Cowley, before heading east (just north of the M40) close to the Regents Canal, through Bull’s Bridge eventually to Brentford, where the Grand Union meets the River Thames.
You can find out more about our cruise guides and waterways maps on our canal boat holiday base information pages canal boat holidays in Oxfordshire and canal boat holidays in Warwickshire.
Feats of Engineering on the Grand Union
The Hatton Flight
The 21 locks in the Hatton flight are nicknamed ‘the stairway to heaven’, a reference made to when workers had to make their way to the top in order to get paid! These locks and the rest of the main line of the Grand Union Canal was part of a last gasp effort, backed by the government of the day, to modernise the canals so they could compete with road and rail. It took two years and 1000 men to rebuild the 21 Hatton locks alone, using the new material, concrete.
Located on the Grand Union Canal in Leicestershire, these locks comprise of two staircases with 5 locks each. Built in 1810, these locks are a spectacular feat of engineering and carry a Grade II listing. They raise boats up to 75ft in approximately 45 minutes.
Foxton Inclined Plane
Foxton is the site of a steam powered ‘Inclined Plane’, an idea to replace the ten existing locks and lift narrowboats 75 feet. It was opened in 1900 but suffered from mechanical and structural problems and the locks were reopened in 1908. You won’t find this on canal maps now, although you can see the remains of the Plane as you ascent / descent the locks along the side.
The 7 narrow beam Watford locks lift the Grand Union Leicester Arm 16 metres to the Leicester summit level. They were opened in 1814 and there have been schemes to widen them from 7 foot to 14 foot ever since. They, with Foxton Locks at the other end of the summit level, are the main barriers preventing wide beam boats and barges reaching the waterways of the midlands and north.
Opening in 1805, Blisworth Tunnel in Northamptonshire is the third-longest navigable canal tunnel on the UK canal network after Standedge Tunnel and Dudley Tunnel (and the ninth-longest canal tunnel in the world) at 3,076 yards (2,813m) long. At its deepest point it is ca.143 feet (ca.43m) below ground level.
The Iron Trunk
At Cosgrove on the borders between Buckinghamshire and Northamptonshire, the Grand Union Canal crosses the River Great Ouse via an aqueduct. This cast iron trough, known as the ‘Iron Trunk’ was built in 1811, to replace a previous brick structure that had failed. The structure has two cast iron trough spans, with a single central masonry pier. The trough is 15 feet (4.6 m) wide, 6 ft 6 in (1.98 m) deep, with a total length of 101 feet (31 m). The canal surface is about 40 feet (12 m) above the surface of the river. There are large approach earthworks about 36 feet (11 m) high above the valley floor and 150 feet (46 m) wide, with a total length of half a mile (800m).
Connecting the River Brent to the rest of our canal system, today, Hanwell’s flight of seven locks is located in West London. This flight of seven locks is located next to St Bernard’s Hospital and has features such as lock keeper’s cottages and a ramp to help horses out of the canal when they fell in.
The ‘Arms’ and ‘Branches’ of the Grand Union
The Grand Union Canal which starts in the centre of Birmingham and provides a continuous route to West London also has a variety of Canal Arms and Branches.
- Wendover arm (1799)
- Paddington (1801)
- Buckingham (1801)
- Northampton arm (1815)
- Aylesbury (1815) The canal to Newport Pagnell (opened 1817) was built by a separate company
- Slough Branch was one of the last canals to be built (1882)
The Leicester Section
The Leicester section branches north at Braunston and climbs a little less steeply before falling to join the River Soar just after Loughborough. The canal section before Leicester is very rural at times and has two tunnels at Crick and Husband’s Bosworth and staircase locks at Watford and Foxton. It includes the Market Harborough arm which is very popular for canal runs and canal walks.
Norton Junction is a major waterways place at the junction of the Grand Union Canal (Leicester Section – Old Grand Union) with the Grand Union Canal (Grand Junction Canal – Main Line – Braunston to Norton) and the Grand Union Canal (Grand Junction Canal – Main Line – Norton to Gayton).
Did You Know?
Black Prince Cruising Routes
You can cruise on the Grand Union Canal starting from our bases at Napton in Warwickshire and Stoke Prior in Worcestershire. Check out our canal maps and cruise guides on our base page for waterways guides and more information for your canal holiday.
Napton Canal Hire Base – a cruise guide
From our base at Napton in Warwickshire you can start your canal boat holiday on the Grand Union South, a return trip to Leighton Buzzard and back over a week. This is a real countryside cruise taking you south through pretty scenery to Stoke Bruerne, home of the Waterways Museum, a pretty pub, cafe and ice-cream parlour! Continue south over the River Ouse Aquaduct to Leighton Buzzard before turning and returning home. A longer cruise will enable you to continue to Tring, Berkhamsted and Kings Langley.