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Alcatraz Island, which is a designated National Historic
Landmark District, is a part of the Golden Gate National
Recreation Area administered by the National Park Service.
For over 90 years, Alcatraz Island has been dominated
by the reinforced concrete Cell House and together,
the island and the prison are one of the most prominent
and important landmarks in the San Francisco Bay
Area.
The Cell House also receives close to 1 million visitors
a year. Acting proactively in the mid-nineties, the
Park Service and its non-profit arm, the Golden Gate
National Parks Conservancy along with the Blue and Gold
Fleet (a park partner), sought a solution for providing
access to its main entrance to individuals with disabilities.
Up to that point, disabled visitors had to enter the
building from a remote side entrance because of an eight
inch step at the front entrance. The park service initially
supported a two ramp solution at the front entrance
because they wanted to leave in tact the heavily worn
plaza that was important historic fabric. Lerner +
Associates proposed a universal design solution that
essentially warped the plaza at the entrance by installing
a semicircular concrete walkway (1:23 slope) that led
to a semi-circular level landing at the entrance. A
slip sheet was first applied over the existing concrete
to protect it in the event the new concrete was ever
removed (a reversible design solution). To help the
semi-circular element blend in with the rectangular
plaza, the concrete was scored to match the rectangular
pattern of the original plazas concrete. In time,
when the concrete ages, the slight curve of the new
concrete will fade in contrast. Now all visitors including
disabled, frail, and mothers with baby carriages can
all enter the cell house using the same entrance without
calling attention to any special means for them, a truly
Universal Design solution.
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