Efforts to save Bletchley Park, the historic site where wartime code-breakers cracked the Germans' infamous Enigma code, from further disrepair have been given a boost by a donation of $100,000 (£57,000) from two large American hi-tech firms.

The donation from technology companies IBM and PGP will be put to restoring and curating collections at the National Museum of Computing, which is contained on the Bletchley Park site. Notable exhibits include a model of Colossus, generally acknowledged to be the world's first computer, which was operated on the site from 1943, as well as an original Enigma coding machine, used by the Germans to encrypt mesages during the Second World War.

Concern has been mounting as to the future of the site, after an appeal for funding to the Bill & Melinda Gates Foundation was turned down in May. Since then, a petition on the Downing Street website has gathered over 14,000 signatures in support of measures to protect the site, and in July, 97 academics wrote a letter of protest arguing that "the future of the site, buildings, resources and equipment at Bletchley Park must be preserved for future generations."