Washington Monument vs. Gateway Arch: Which Is Tallest?

The Washington Monument (Washington, D.C.) is the tallest stone structure and tallest obelisk in the world at 555 ft 5⅛ in (169.29 m). It is the tallest monument in Washington, D.C.

However, it is not the tallest monument in the United States. That title belongs to the Gateway Arch in St. Louis, Missouri, which stands at 630 ft (192 m)—75 feet taller.

Key Distinction

• Washington Monument: Commemorative obelisk (stone/masonry).
• Gateway Arch: Architectural monument (stainless steel catenary arch).

Both are iconic national symbols, but the Arch claims the height record for "monument" in the US. Globally, the Juche Tower (Pyongyang, 170 m) and San Jacinto Monument (Texas, 173 m) also surpass the Washington Monument.