The hidden river flowing underneath Bristol city centre

With news that one hidden river in south Bristol is set to be unearthed, it is time to reopen a debate that has raged for generations: could the River Frome be restored to its former glory?

We have got our medieval forebears to thank for its disappearance.

Where once the Frome (it rhymes with ‘zoom’) ran through the city, it is now mostly hidden from view under our feet; but it still flows freely beneath city centre streets.

“Over the years, Bristolians have forced the Frome to adapt to their changing needs,” writes Sally Watson in her book, Secret Underground Bristol.

“They have altered its course, blocked it up here and channelled it off there, used it as a defence, a harbour and a sewer, and finally, when it became a nuisance, they buried it.

“The history of the Frome is a miniature history of Bristol.”

The River Frome disappears from view next to Wade Street in St Jude’s close to Cabot Circus car park – photo: Martin Booth

This grate next to the Watershed is where the Frome flows into the Floating Harbour after travelling underground from St Jude’s – photo: Martin Booth

River Street in St Jude’s is a clue as to where the underground section of the Frome starts, close to Cabot Circus car park.

It flows underneath Broadweir, follows the path of Rupert Street and Fairfax Street, goes underneath what we now call the centre, and comes out next to the Watershed.

St John’s Bridge between Rupert Street and Lewins Mead is a sign of what is beneath our city’s streets, and it is not the only almost-intact bridge originally built to cross the River Frome but now hidden underneath modern roads.

St John’s Bridge is a clue as to what lies beneath – photo: Martin Booth

The original course of the Frome followed the line of St Stephen’s Street and Baldwin Street, with the Frome and the Avon creating the natural fortifications for Bristol Castle.

Water from the Frome later fed the castle’s moat, with the last visible section of it emerging from a brick arch close to the new Castle Park View tower.

Built in the 11th century by Robert the first Earl of Gloucester, Bristol Castle was once the largest Norman castle in England – illustration by Christine Molan

Castle Ditch Bridge spans the last visible part of Bristol Castle’s moat – photo: Martin Booth

According to Watson, “using the Frome to supply the castle moat (in the eleventh or twelfth century) was probably the first large-scale manipulation of the river, but soon afterwards the demands of commerce prompted an even more ambitious project”.

This was diverting the last stretch of the river from its original course, creating a huge new trench to join the Avon further downstream next to what is now the Arnolfini.

The Frome was open all along its length until 1858 where it was crossed in the city by 13 bridges, some of them dating back to medieval times.

Stonebridge House near Christmas Steps and the Drawbridge pub are two reminders of these crossings, and it was from Stone Bridge to Wade Street in St Jude’s that the Frome was covered over with brick culverts during the second half of the 19th century.

Much of St Augustine’s Trench was covered over in 1893 to create space to host the Industrial & Fine Arts Exhibition before becoming the tramways centre.

St Mary-on-the-Quay church and Quay Head House (today occupied by the Milk Thistle) are two clues here of when the Frome was above ground almost to modern-day Electricity House.

Ships were able to moor directly in front of the Hippodrome when the theatre opened in 1912, with this section of the trench covered in 1938.

Now only the last stretch of the diverted Frome between the Watershed and the Arnolfini remains above ground.

A rare lifting of Pero’s Bridge over the last section of the River Frome as it flows into the original course of the River Avon – photo: Martin Booth

Main photo: Martin Booth

Take a walk around the hidden corners of the Old City with Martin Booth and Yuup. Use promo code HAPPY10 to get £10 off this and all other Yuup experiences until January 16: www.yuup.co/experiences/explore-bristol-s-quirkiest-corners

Read more:

• Exploring beneath Bristol streets
• Historic river flowing through Bedminster set to be unearthed
• Following the Frome

Listen to the latest Bristol24/7 Behind the Headlines podcast: