 By the start of the 20th century it was clear that Gibraltar could be bombarded with relative impunity from the Spanish mainland. Proposals were put forward to build a new harbour on the east side of the Rock, where ships would be less vulnerable to direct artillery fire from the mainland, but were abandoned due to the vast expense and only marginal gains in security. A new round of tunnelling was carried out to provide more bombproof accommodation for the garrison, along with deep shelters and casemates capable of accommodating 2,000 men. Ultimately it was decided in 1906 that Gibraltar faced no credible threat from land and that the defences would be organised to deal with a threat from the sea.
