Ministry of Justice figures show there were 667 trials listed at the court in 2021 – with 35% having to be adjourned, up from 29% the year before, and the most since records began in 2010.
The figures show a further 31% saw the Crown Prosecution Service drop the case or the defendant pleaded guilty and 34% of trials went ahead as planned.
Of the 21,805 crown court trials nationally last year, just 48% went ahead as planned – the lowest proportion in a decade.
The Law Society of England and Wales said victims are facing are "unacceptable" delays and some are being forced to wait years for justice, while potentially innocent defendants are also left in limbo.
Stephanie Boyce, President of the Law Society, said the coronavirus pandemic is one factor, but lack of capacity in the system is another.
She said: "Decades of underfunding and cuts mean there simply aren’t enough judges, prosecutors and defence lawyers left to cover the huge backlog of cases.”
She said swift investment is needed across the criminal justice system to get it back on its feet.
The Ministry of Justice spokeswomen said it has spent nearly half a billion pounds in court recovery.
A spokeswoman added: “While the unprecedented impact of the pandemic has led to large numbers of court staff and counsel falling ill or being forced to self-isolate, our decisive action has kept justice moving."