Alcatraz, the island in San Francisco Bay best known for its history as a federal penitentiary, has long been a site of layered significance — from its role as a Civil War defense fort to its place in modern history as the location of the 1969 Occupation by Native American activists, which influenced later federal policies on Indigenous rights. Now part of the National Park system, the island—often called “The Rock”—hosts a new temporary installation titled Shortening: Making Irrational Rational, presented by the National Park Service in collaboration with artist-mathematician Nelson Saiers, Ph.D.
Based in New York, Saiers creates work that investigates the world’s mysteries through the lens of mathematics. For this installation, he explores the relationship between numbers and prison sentences — the numeric identifiers inmates sometimes call “football numbers.” The project displays the first 200 digits of Pi on football jerseys, turning an abstract mathematical constant into a visual and historical commentary on incarceration. One of the jerseys bears the number 85 on a Chicago Bears uniform, a reference to the number once associated with Al Capone during his imprisonment on Alcatraz.
Visitors can include the exhibition as part of the standard Alcatraz tour experience. Access to the island is provided by Alcatraz Cruises, with departures from Pier 33 in San Francisco. Admission to the Alcatraz tour includes entry to the installation, allowing guests to experience the artwork alongside the island’s many historical sites and interpretive exhibits.
The installation continues the island’s tradition of combining history, protest, and reinterpretation. By presenting Pi’s digits on items associated with identity and confinement, Shortening: Making Irrational Rational invites reflection on how numerical systems intersect with human lives, how labels are applied and perceived, and how sites like Alcatraz carry multiple, sometimes competing, narratives.
When planning a visit, check Alcatraz Cruises for current departure times and ticketing options for tours that include exhibition access. The island’s layered history — military fortification, notorious federal prison, and site of Indigenous protest — provides a powerful backdrop for installations that ask visitors to reconsider familiar symbols and stories through new, creative perspectives.
