It took a month to pluck up the nerve, but on a soggy grey morning in June we headed upriver. Sabrina, to defer to the River Severn’s Roman deification, is a mistress not to be messed with lightly, and ‘heading upriver’ has the uncomfortable ring of some dread euphemism, like ‘crossing the rainbow bridge’. To be fair, rafts of driftwood are a far more common site than boats rendered into rafts by the semi-tidal river. But anxiety is rarely troubled by rational thinking, and there was a fright on the journey downriver the previous October when my little narrowboat Jimbo lost power, by sheer luck within drift range of a small wharf at Ashleworth. There followed a winter of mechanical discontent on the Gloucester and Sharpness Canal, but much fussing and fixing in the engine bay never did bottom out all the issues. Jimbo still puttered into Gloucester lock with a worrying guttural warble.

The lock is a cavernous space, and the lock keeper was very patient as we bounced like an echo off the left wall, drifted over to the right wall and then battled our way back to the left. I needed to hold Jimbo portside to the wall while the lock was flushed because the starboard centreline had been redeployed as an essential component in keeping anchor attached to boat.

Great British Life: Narrowboat heading upriver from Gloucester Locks (c) Mark HarrisonNarrowboat heading upriver from Gloucester Locks (c) Mark Harrison Great British Life: The Quay on a flooding River Severn outside Gloucester Docks (c) Mark HarrisonThe Quay on a flooding River Severn outside Gloucester Docks (c) Mark Harrison

Once the slow descent to river level was complete, towering oak gates parted down the middle, the vertical seam of light slowly widening into a tunnelled vista of the river ahead. Thick foliage above a thin band of silt lined the left bank, while to the right the high stone wall of The Quay extended all the way to a distant bend. We eased out from safe harbour like children venturing out into a world both exciting and scary. The plan for the day was to make the eight miles to Haw Bridge before the forecast heavy rain started to fall or, I couldn’t help fretting, Jimbo failed.

If it were possible to condense two millennia into a fleeting moment, then we would have been part of an eclectic fleet, our crawl past The Quay in the company of diesel-driven barges, horse-drawn narrowboats, twin-masted brigs, single-sailed trows, even oared Roman rates. A quay has been a feature on this part of the river since the 14th century, and between Elizabethan elevation of Gloucester to a port and the opening of the Docks in 1827 it was the city’s port facility. The Quay today is now simply a high wall, though when Sabrina has a mind to, it becomes a low river wall. Frequent flooding ensures that Alney Island, formed by the two channels of the Severn on the western edge of Gloucester, will never be much more than meadows and fields bisected by causeways ancient and modern, and even before we had passed under the last of the small city’s bridges, the urban sprawl to the east had wisely peeled away from the river.

Great British Life: The River Twyver joining the River Severn just above Gloucester (c) Mark HarrisonThe River Twyver joining the River Severn just above Gloucester (c) Mark Harrison

A Google Maps-eye view of the countryside north of Gloucester through which the Severn meanders reveals a tree-lined corridor threading through a patchwork of fields. The boat-eye view, though, is of dense foliage with few glimpses beyond. It all felt very Heart of Darkness. The river is, to be sure, an aquatic artery without the hostile natives of Conrad’s tale, but leaving civilisation in our wake was a little unsettling. There’s no easy parking should something go wrong. Soaking up a privileged perspective on the lush riparian scenery gliding by played second fiddle to searching out boughs which at any given moment might be both accessible enough and solid enough to be pressed into service as emergency moorings. The anchor was a last resort; being rooted to the riverbed in the middle of the narrow channel would have been a tad inconvenient for the large hotel boat that would be heading downriver later in the day.

Jimbo is a simple vessel, and the only instruments on board to monitor engine health are eyes and ears. When my head wasn’t in the trees it was in the engine bay, listening for indications of stress or checking that coolant was not steaming or geysering. The frequent inspections required me to crouch down and lift a deck panel, a distraction Jimbo invariably saw as an opportunity to head for the trees.

After an hour of anxious cruising, the point at which east and west channels separate crept into view. Our arrival at Upper Parting brought some small relief, though Jimbo’s warbling dipping briefly into the lower registers just as we reached the mouth of the more voracious west channel concentrated the mind a little. Maisemore weir a short distance down-channel is a fearsome beast.

Great British Life: Maisemore Weir on the West Channel of the Severn below Upper Parting (c) Mark HarrisonMaisemore Weir on the West Channel of the Severn below Upper Parting (c) Mark Harrison

The river above the parting is wider and a little slower than the east channel we’d just nervously navigated, which allowed me to step down a notch on both throttle and anxiety. While my head still flitted between engine and treelines, there was more capacity to soak up the untamed beauty through which we passed. It was a beguiling corridor of green and grey untainted by human meddling, a hectic 21st century held at bay behind thick verdant walls. The patter of gently persistent rain on raincoat hood provided the rhythm section to a soundtrack of bird song and internal combustion. With Jimbo plugging gamely away, moments of serenity surfaced up through the anxiety, like pockets of air bubbling up from a swamp.

Almost two millennia ago the Romans effectively graffitied the riverbank at Ashleworth with “Caesar hic erat”, in the form of the archaeological remains of the quay they built there. Until the mid-20th century there was an ancient ferry which, according to legend, could count among its many passengers over the centuries a fleeing king or two. On the river below the Boat Inn, which since the floods of 2020 has been a redundantly named private residence, there is the small wharf that had served us so serendipitously the previous year. I had thought to break up the journey with a stop there at the end of the second hour, but the fear of imminent disaster was fracturing like stone penetrated by woodland roots, and we continued on towards the Red Lion at Wainlodes.

Great British Life: The River Severn at Wainlodes (c) Mark HarrisonThe River Severn at Wainlodes (c) Mark Harrison

The name Wainlode betrays at some period in the past the existence of a ford by which wagons crossed the river. Tacking an ‘s’ onto the end appears to be one of those etymological tricks which betrays anyone who talks in the singular as “not from roun’ yer.” The Red Lion is the sole surviving riverside pub between Gloucester and Haw Bridge, the lawn out front well-frequented, in good weather by customers, in bad by Sabrina. It was on a childhood family visit that the seeds of an enchantment were sown. In that corner of my now wisening mind where time is malleable, I could see myself standing at the river’s edge, gazing raptly downriver, as if the child at the other end of my life was watching us approach.

Soon after rounding the Wainlodes meander, we passed in quick succession the confluence of the Chelt – a small river which gave its name to a ham that grew up to be a town – then the concealed entrance to an ill-fated venture that fell well short of extending late-18th century canal mania to Cheltenham. Coombe Hill Canal, the name betraying not only the nearest the canal came to the town but also the reason why it did not get any nearer, was abandoned after eighty unprofitable years when a flooding Sabrina dismantled the lock, putting it beyond economic repair.

We were on the home straight, though these things are relative. The meandering river became -for the rest of the day’s journey - merely a bit bendy, and not long after our trip ticked over into its fourth hour, Haw Bridge edged out from the treeline. The Severn was first spanned where previously a ferry had shuttled in 1825, though the original bridge was brought down in 1958 by an empty fuel barge riding high on a high river. That fatal collision was joined in the ledger of man versus Sabrina by another, two years later near Sharpness, when two laden barges from the same fleet brought down upon themselves the Severn Railway Bridge and turned the night fog incandescent.

It was no small sense of achievement to secure Jimbo safely to the pontoon below the Haw Bridge Inn (another misnomered residence) and shut down the engine. It proved to be a well-judged trip, and not just because it turned out to be within Jimbo’s suspect capabilities. Not long after our arrival, as another narrowboat joined us on the pontoon (the crew, it would transpire the next day, a couple of angels) the steady persistent rain became a deluge. It was something special to stand in the shelter of the door to what is effectively a floating castle, watching the heavens plunge into the Severn.

Great British Life: Pontoon at Haw Bridge (one of the few safe moorings on the Severn above Gloucester) (c) Mark HarrisonPontoon at Haw Bridge (one of the few safe moorings on the Severn above Gloucester) (c) Mark Harrison Great British Life: The River Severn from Haw Bridge (c) Mark HarrisonThe River Severn from Haw Bridge (c) Mark Harrison