Two trenches have been opened – exposing parts of the brick structure – and investigations are due to take place throughout September.

To coincide with Heritage Open Days, there were two open days earlier this week at the site with the walls of the blockhouse marked out on the ground and finds displayed, while members of the Humber Field Archaeology team were on hand to answer questions about the discoveries.

In July, there was a similar event where the walls were marked out for a two-day period and pupils from Victoria Dock Primary School were able to learn more about the site and design cannons with Jon Kenny, a specialist community archaeologist from Historic England.

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As the investigations are carried out during September, there will be weekly open days on Tuesdays 12^th, 19^th and 26^th September, where the results of the work will be updated.

Ken Steedman, project manager at Humber Field Archaeology, said: “This is a hugely exciting excavation.

“Henry VIII chose to build the south blockhouse to defend the city of Hull because of its significant strategic position.

“When we worked on the site in 1997, we discovered an iron-breech loading cannon similar to those recovered from Henry’s sunken warship the Mary Rose, which is now in the Hull and East Riding Museum.

“We may not find anything quite as large or exciting as that this time, but we are anticipating uncovering some very useful information about the blockhouse.”