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A competition-winning assemblage of design teams has banded together to rejuvenate and enlarge the Eero Saarinen-designed Museum of Westward Expansion below St. Louis' iconic Gateway Arch. With landscape architecture by Michael Van Valkenburgh Associates, the team of Cooper Robertson, James Carpenter Design Associates and Trivers Associates has transformed 105,800 square feet of the existing building while adding a further 4,366 square feet to its footprint.
Now known as the Museum of the Gateway Arch, the subterranean space has been remade under the explicit project goal of increasing connectivity between Luther Ely Smith Park, the Old Courthouse and downtown St. Louis. Previously, the six-lane Interstate 44 separated these city landmarks from each other. The team created a landscaped green space over the highway as a solution that now links these nodes and creates a seamless pedestrian experience.
"The new West Entry and Museum expansion is discretely incised into the landscape," said James Carpenter, founder and principal of James Carpenter Design Associates, "This welcoming gesture is announced by an arc of glass laid flat on the ground, reflecting the image of the sky above, while the Arch itself scribes an arc against the sky beyond."
A semi-circular enclosed glass volume marks the entry to the below-ground Museum Arrivals Hall, with entering visitors guided by a luminous ceiling that follows the topographic slope. The entire project, including updates to the park, cost $380 million and took about five years to finish.
