One answer to this question may be ‘mainly clay’ but, as our subterranean passageway correspondent Angus Young reveals, there are some navigable spaces.
Pub quiz fans will know that no other city has so many operating bridges over such a short stretch of navigable river than Hull. There are 13 of them – including two bridges at both Kingswood and Stoneferry which can actually operate independently of each other. Just to be clear, we’re not including Scott Street bridge in the total because most of the structure was removed a couple of years ago and only a few riverbank supports remain.
What is less known is that a number of tunnels also run under the river. We’re not talking about the ill-fated Ennerdale Tunnel, which flooded during construction and was ultimately abandoned in favour of building a road bridge. Instead, a couple of lesser known service tunnels run under the riverbed connecting West and East Hull. A recent Hull City Council decision record report shed new light on one of these subterranean routes.
The report authorised a survey and structural tests to be carried out on an existing tunnel under Drypool Bridge. The work aims to ensure the tunnel is in a fit state to carry pipework needed for a proposed future underground district heating network covering the city centre and, in particular, a major new housing development earmarked on the river’s east bank at the site for the former Clarence Mill. It’s also been timed to coincide with the programme of repairs to the bridge itself which starts this week and is expected to take several months.
The Drypool Bridge service tunnel isn’t the only one under the river. Similar tunnels carrying various utility pipes and cabling also run under North Bridge, Stoneferry Bridge and Sutton Road bridge. There’s also one under the river where Scott Street Bridge once was. Most are large enough to stand up in and are accessed via deep shafts.
Elsewhere, there are a surprising number of underground spaces under the city centre, and the Old Town in particular, despite the once-frequent threat of flooding and the high water table. While there’s a tunnel under the lock gates at Hull Marina and another linking Paragon Station to the Royal Hotel next door, most are mainly vaults and storerooms connected to buildings above.
A vast subterranean cellar lies under the Dram Shop pub in George Street while the basement and strong room under Ocean Chambers in Lowgate was built in 1889 by the same company that installed the original vaults at Harrods department store in London. On the opposite side of Lowgate, St, Mary’s Church boasts a substantial underground crypt and legend has it that a number of tunnels once ran from Ye Olde Black Boy in High Street to the River Hull.
Public realm improvement work carried out in the build-up to Hull’s year as the 2017 UK City of Culture uncovered a brief glimpse of the remains of the basement Ye Mecca cafe which once operated under the bombed Prudential Tower overlooking Queen Victoria Square.
However, the square still provides one of Hull’s best underground experiences in the shape of the toilets under the statue of the old queen herself. Built in 1925 along with the statue, the loos were awarded Grade II listed status in 1994 for their historic and architectural significance.