After Spain declared war on Britain on 21 June 1779, Gibraltar was besieged by land and sea for four years. The centrepiece of the siege was the dramatic assault by supposedly invincible battering ships and the author reveals how these floating phenomena were countered by British engineering ingenuity and sheer resolve. In this detailed account of the siege, Rene Chartrand examines the Franco-Spanish and British forces as well as the personalities and plans that would contribute to a vital British victory at a time when British fortunes elsewhere in the world were on the wane.