Flights of fancy: Hanwell locks – London

This attractive flight of locks, as painted by Turner, take the Grand Union Canal down to the Thames

Photo: Maxwell Hamilton


Lock flights were created as the best and most practical means of getting canals up and down steep hills. Sometimes, the engineers laying out the canals decided it was easier to go up a hill rather than round or through it – and that’s where the flight comes up, a series of locks in short succession that allows the canal to navigate more dramatic inclines.

London’s principle flight is at Hanwell, far to the west of the city. The six locks were built in 1794 to take the Grand Union down to the Thames, and the locks are also close to the fascinating Three Bridges, constructed by Isambard Kingdom Brunel to combine road, rail and canal. As well as these industrial marvels, there’s also lots of nature to explore as the locks adjoin ponds and meadows.

As the Grand Union descends from London, it divides at Bull’s Bridge, with one arm heading towards Paddington where it joins the Regent’s Canal and the other continuing south, where it meets the Brent before hitting the Thames. This second arm was the first to be built, with the London extension coming almost as an afterthought a decade later. Getting to the Thames was seen as vital, and the canal here was lined with wharves and jetty.

The biggest engineering challenge came at Hanwell, where the six lock flight allowed the canal to move downhill towards the Thames valley, a descent of 53 feet in around a third of a mile and one that can take boats over an hour to make. This featured in a painting by JMW Turner, who in 1810 painted the canal at Hanwell, with lock in the foreground and windmill behind, a surprisingly rural look for such an industrial area.

At this point, the canal also passed the County Asylum, which had a wharf for boats to deliver coal and take away fruit and veg from the inmates’ gardens. This is now bricked up. Following the bottom lock at Hanwell, the canal joins the canalised Brent and flows into the Thames. The recently restored Hanwell Flight is now a Scheduled Ancient Monument, and there’s plenty for visitors to see and do. Have a look on our website to help plan your day.