Alcatraz Island Engineers began fortifying the island, work which continued until 1858, eventuating in Fortress Alcatraz. The island's first garrison at Camp Alcatraz, numbering about 200 soldiers and 11 cannons, arrived at the end of that year. When the American Civil War broke out in 1861, the island mounted 85 cannons (increased to 105 cannons by 1866) in casemates around its perimeter, though the small size of the garrison meant only a fraction of the guns could be used at one time. At this time it also served as the San Francisco Arsenal for storage of firearms to prevent them falling into
Occupation of Alcatraz at 47 cents per acre, this amounted to $9.40 for the entire rocky island, or $5.64 for the twelve usable acres. Cottier also stated that the federal government would be allowed to maintain use of the Coast Guard lighthouse located on the island. The protesters left under threat that they would be charged with felony. This incident resulted in increased media attention for indigenous peoples' protests across the Bay Area. The United Council of the Bay Area Indian community initially considered writing a proposal and filing an application for the use of Alcatraz by Sioux people under the conditions of