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Letter from Alcatraz

Inside the Rock's Surprising History

Before it was an infamous prison, Fort Alcatraz played a key role defending the West Coast

September/October 2020

Alcatraz IslandOn the 8:20 a.m. boat to Alcatraz, no one gawks at the spectacular views of San Francisco along the shore of the bay. It’s cold and overcast, as is typical for late spring. The conversations are familiar and collegial—this ferry is limited to people who work on the island, including National Park Service rangers, volunteers, and maintenance personnel. The 22-acre rocky island of Alcatraz is less than two miles north of downtown San Francisco, so the journey lasts only about 10 minutes. Since the maximum security Alcatraz Federal Penitentiary closed in 1963, after just under three decades of operation, the prison’s picturesque location and former celebrity inmates have generated reams of tourism-industry copy, inspired numerous Hollywood films, spawned urban legends, and made Alcatraz Island one of America’s most popular National Park Service sites. Yet few know about the island’s pre-prison history.


Alcatraz MapThe first European to visit Alcatraz is thought to have been the Spanish explorer Juan Manuel de Ayala, who sailed his ship San Carlos into San Francisco Bay in August 1775 and named one of its islands Isla de los Alcatraces, “Island of the Pelicans” or “Strange Birds.” In the mid-nineteenth century, the island became home to Fort Alcatraz, one of the first U.S. military fortifications constructed on the West Coast. It was also the site of the West Coast’s first lighthouse.


San Francisco Bay was formed only 10,000 years ago, as sea levels rose following the last Ice Age. Since then, the inhospitable Alcatraz Island has offered little to entice humans away from the temperate climate and abundance of natural resources on the mainland surrounding the bay. Except for an obsidian tool that archaeologists are nearly certain came to Alcatraz in imported soil, they have not found any artifacts dating from before Europeans first arrived in the late eighteenth century. An American army officer once described the island as “entirely without resources within itself and the soil is scarcely perceptible, being rocky and precipitous on all sides.” In 1847, Alcatraz’s first surveyor, W. H. Warner, wrote, “This Island is chiefly composed of irregularly stratified sandstone covered with a thin coating of guano. The stone is full of seams in all directions which render it unfit for any building purposes and probably difficult to quarry.”