Among the most notable architectural features in the Supreme Court Building are two self-supporting, elliptical marble staircases. Whether Cass Gilbert, the building’s architect, chose to include them for practical reasons or simply for their visual beauty is unknown.
Each of the staircases has 136 steps, completing seven spirals while rising five stories from the basement to the third floor. The staircases are cantilevered in design, eliminating the need for a central support as each step is anchored to the marble wall and rests upon the step below t. The staircases, therefore, are held in place by fit and pressure rather than mortar and steel.
The bronze railings for the stairs are adorned with a classical wave pattern, rosettes, and oval medallions featuring an eagle, a symbol of the United States.
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