There are well over 50 tunnels on the canal network, ranging in length from 25 yards (23 metres) to over three miles (5,210 metres).

The construction of tunnels was one of the most difficult tasks faced by the early canal engineers, and the dangerous and difficult work led to the death of many navvies, including 14 when a section of the Blisworth Tunnel collapsed in 1896.

To celebrate these engineering marvels, we’ve published a guide to the six longest canal tunnels in England and Wales:

1. The Standedge Tunnel (5,210 metres/5,698 yards)

Tunnelling for 3.24 miles beneath the Pennines, this incredible feat of 18th and 19th century engineering is the longest, highest and deepest tunnel on the canal system.  Cutting through solid rock, it took the navvies 16 years to build and opened in 1811.  In the 20th century, the Huddersfield Canal fell into disrepair, becoming un-navigable by 1948, but after a long restoration programme, both the canal and tunnel were reopened in 2001.  It takes around 1 hour and 20 minutes to navigate through Standedge Tunnel.  Narrow boat holiday-makers need to book their passage though with a Canal & River Trust chaperone.  Drifters’ nearest base is at Sowerby Bridge, on the junction of the Calder & Hebble Navigation and Rochdale Canal, is 20 miles and 65 locks away. The journey to Standedge takes around 21 hours (three days).

2. Blisworth Tunnel (2,794 metres/3,056 yards)

At 1.74 miles long, Blisworth Tunnel on the Grand Union Canal at Stoke Bruerne in Northamptonshire is the second longest navigable tunnel on the canal system.  Construction began in 1793, and it was opened in 1805.  It’s wide enough to accommodate two narrowboats, so it’s not necessary to book a passage through it.  From Drifters’ base at Gayton on the Grand Union Canal in Northamptonshire, it takes around 38 minutes to reach the northern entrance of the Blisworth Tunnel.

3. Netherton Tunnel (2,768 metres/3,027 yards)

Tunnelling for 1.72 miles, Netherton Tunnel is on the Birmingham Canal Navigations Netherton Branch in Birmingham.  It was the last tunnel constructed during the canal age, and was built with towpaths on both sides.  From Drifters’ canal boat hire base on the Worcester & Birmingham Canal at Alvechurch, it takes around eight hours to reach Netherton Tunnel, cruising 19 miles of waterway.

4. Harecastle Tunnel (2,676 metres/2,926 yards)

Harecastle Tunnel on the Trent & Mersey Canal is 1.65 miles long and it takes around 30 minutes to navigate through.  Designed by Thomas Telford, it was completed in 1827. Passage through the tunnel is in a single direction at a time, because only one of the two original Harecastle Tunnels is in operation. Access is controlled by the Canal & River Trust’s Tunnel keeper team, allowing groups of boats to pass through in convoy, before reversing the flow of traffic.  From Drifters’ narrowboat hire base at Stoke on Trent it takes around one and a half hours to reach the southern entrance of Harecastle Tunnel.

5. Wast Hills Tunnel (2,493 metres/2,726 yards)

At 1.55 miles long, it takes around 37 minutes to navigate through Wast Hills Tunnel, on the Worcestershire & Birmingham Canal.  Designed by Thomas Cartwright and completed in 1796, Wast Hills is wide enough to accommodate two narrowboats, so it’s not necessary to book a passage through it.  From Drifters’ narrowboat hire base at Tardebigge, it takes about two-and-a-half hours to cruise to the southern entrance of Wast Hills Tunnel.

6. Braunston Tunnel (1,867 metres/2,042 yards)

Braunston Tunnel on the Grand Union Canal in Northamptonshire is 1.17 miles long and was completed in 1796.  It takes around 20 minutes to navigate and it’s wide enough to accommodate passing narrowboats, so there’s no need to book a passage.  With six locks to pass through before reaching the western entrance, Drifters’ canal boat hire base at Braunston is about an hour-and-a-half away.