Missouri Landmarks

The Gateway Arch

The Gateway Arch, also known as the Gateway to the West, is the iconic image of St. Louis, Missouri. The Arch symbolizes St. Louis as a “Gateway” between the east and western United States. It was declared a National Historic Landmark in 1987.

Eero Saarinen

It was designed by Finnish-American architect Eero Saarinen and structural engineer Hannskarl Bandel in 1947.

It stands 630 feet (190 m) tall, and is 630 feet (190 m) wide at its base, making it the tallest monument in the United States.

Construction of the arch started on February 12, 1963 and was completed on October 28, 1965. The monument opened to the public on July 24, 1967.

The cross-sections of its legs are equilateral triangles, narrowing from 54 feet (16 m) per side at the base to 17 feet (5.2 m) at the top.

Apex of the Gateway Arch

Gateway Arch, Southern Base

During construction, both legs were built up simultaneously. The base of each leg at ground level had an engineering tolerance of one sixty-fourth of an inch, or the two legs would not meet at the top. When the time came to connect both legs together at the apex, thermal expansion of the sunward facing south leg prevented it from aligning precisely with the north leg. This alignment problem was solved when the St. Louis Fire Department sprayed the south leg with water from firehoses until it had cooled to the point where it aligned with the north leg.

The Observation Deck of The Gateway Arch

The interior of the Arch is hollow and contains a unique transport system leading to an observation deck at the top. Eero Saarinen had decided to incorporate a power lift system to obviate the need to climb 1000-plus stairs. But the shape of the arch would have made a standard elevator impossible. After approaching several elevator companies who failed to come up with a viable method, Saarinen hired parking-lot elevator designer Richard Bowser to do the job. Skeptical city leaders gave Bowser only two weeks to submit a design, but he succeeded. By 1968, a unique tram system that combined an elevator cable lift system with gimbaled cars functionally similar to ferris wheel gondolas had been installed. (The interior of the Arch also contains two emergency stairwells of 1076 steps each.)

The Gateway Arch is the tallest habitable structure in Missouri, 7 feet higher than the 623 foot spire of One Kansas City Place in Kansas City, and 37 feet higher than the roof of Metropolitan Square in St. Louis, Missouri.

Eero Saarinen died from a brain tumor four years before the Arch was completed.

From the visitor center, one may move to either base of the Arch (one on the north end and the other on the south end). The north base includes displays which interpret the design and construction of the Gateway Arch; the south base includes displays about the St. Louis riverfront during the mid-19th century.

Gateway Arch Tram Car

Passing through the tramway doors from either base, passengers in groups of five enter an egg-shaped compartment containing five seats and a flat floor. Because of the car shape, the compartments have sloped ceilings low enough to force taller riders to lean forward while seated (for this reason it’s recommended that the tallest of the five passengers in the car sit in the center seat facing the door). Eight compartments are linked to form a train, meaning that both trains have a capacity of 40, and that 80 people can be transported at one time. These compartments individually remain level by periodically rotating 5 degrees at a time, which allows them to maintain the correct orientation while the entire train follows curved tracks up one leg of the arch. The trip to the top of the Arch takes four minutes, and the trip down takes three minutes. The car doors have narrow windows, allowing passengers to see the interior stairways and structure of the Arch during the trip.

Near the top of the arch, you exit the compartment and climb a slight grade to enter the arched observation area. Thirty-two small windows (16 per side) measuring 7 by 27 inches (180 mm × 690 mm) allow views across the Mississippi River and southern Illinois, with its prominent Mississippian culture mounds to the east at Cahokia Mounds, and the City of Saint Louis and St. Louis County to the west beyond the city. On a clear day, one can see up to thirty miles (48 km).

The Gateway Arch

The Arch is in the shape called a catenary, but upside down. (A chain that supports only its own weight forms a catenary.) An inverted catenary arch that supports only its own weight is strictly in compression, with no shear. The shape is therefore ideal.

A time capsule containing the signatures of 762,000 St. Louis area students was welded into the keystone before that final piece was set in place.

The Arch has attracted many stunts, some successful, others fatal:

Eleven light aircraft have been successfully flown beneath the arch, the first on June 22, 1966 when the arch had been completed for less than a year.

In 1980 Kenneth Swyers tried to parachute onto the Gateway Arch, planning to jump off to land on the ground. Instead, he slid all the way down one leg to his death. (The pilot, Richard Skurat, had his pilot certificate suspended for 90 days.)

In 1984, David Adcock of Houston, Texas, began to scale the arch by means of suction cups on his hands and feet, but he was talked out of continuing after having climbed only twenty feet (6.1 m). The next day he successfully scaled the nearby 21-story Equitable Building in downtown St. Louis.