Question: What St. Louis monument built to honor the westward expansion of the U.S. is near a 1.25 oval race track?
Sentence (from "Gateway Arch"): Clad in stainless steel and built in the form of an inverted, weighted catenary arch, it is the world's tallest arch, the tallest man-made monument in the Western Hemisphere, and Missouri's tallest accessible building.
Relevant evidence: No