At 53ft in length and 36 tons, X-51 Stickleback is the only surviving example of four X-Class boats built between 1954-55.They were:

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X51 Stickleback

X52 Shrimp

X53 Sprat

X54 Minnow

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Their design was a upgraded version of the previous WWII XE class midget submarine, famous for their major part in 'operation source',a daring mission to neutralise the heavy German warships – Tirpitz, Scharnhorst and Lützow.

 

Although built for a proposed Cold-War mission, the operation was ultimately cancelled. On 15th July 1958, HMS Stickleback was loaned to Sweden and re-named Spiggen.

 

After being decommissioned in 1977, she spent several years at the Imperial War Museum, before returning home to the Scottish Submarine Centre in 2016.

 

The building which is now the Submarine Centre was once King Street Hall, the annex of St Columba Church. After the front of the building was opened to allow the X-51 to be installed in her new home, a world-class multimillion pound media centre has been constructed around her. This 21st-century technology will be used to tell the story of submarines, from the 19th-century into the future of submarines.