The restoration sought to retain authentic features showing the devastating impact of the 1941 bombing, including the surviving concrete columns, foyer and sections of the auditorium.
Joe Booth, from Hull-based Hobson and Porter, who worked on the project, described it as unique.
“It’s got that level of authenticity, to structurally retain something and leave behind the lasting impact of what happened here.
“As soon as you walk through the front gate, you get that feeling that such a historic event happened here,” he added.
Funding for the restoration was provided by Hull City Council, the National Lottery Heritage Fund, UK Shared Prosperity Fund and the National Civilian World War II Memorial Trust.
In total, about 1,200 people were killed during German bombing raids on Hull, with 3,000 injured and more than 150,000 made homeless.
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