Where did the Royal Navy practise harbour attacks?

Where did the Royal Navy practise Taranto-style tactics?

At Malta, with many practice attacks there, and also at Scapa Flow.

Malta was the principal practice site, and Scapa Flow was also used. These exercises developed skills that the aircrews could combine for the raid. They did not amount to a complete rehearsal of the exact Taranto plan. The operation relied on familiar methods applied to a new target rather than on a wholly improvised attack.