Editing Gateway Arch National Park (section)

===1940s===
The land was to be cleared by 1942.  Among the buildings razed was the "Old Rock House" 1818 home of fur trader [[Manuel Lisa]] (now occupied by the stairs on the north side of the arch) and the 1819 home of original St. Louis pioneer [[Jean Pierre Chouteau]] at First (Main) and Washington streets.<ref>{{cite web|url=http://genealogyinstlouis.accessgenealogy.com/landmarks.htm |title=St. Louis Landmarks |publisher=genealogyinstlouis.accessgenealogy.com |access-date=January 11, 2008 |url-status=dead |archive-url=https://web.archive.org/web/20080407233919/http://genealogyinstlouis.accessgenealogy.com/landmarks.htm |archive-date=April 7, 2008 }}</ref>

The architectural competition for a monument was delayed by [[World War II]].  Interest in the monument was fed after the war as it was to be the first big monument in the post-World War II era.

The estimated cost of the competition was $225,000 and Smith personally donated $40,000.  Civic leaders held the nationwide competition in 1947 to select a design for the main portion of the Memorial space.

Architect [[Eero Saarinen]] won this competition with plans for a {{convert|590|ft|m|0|adj=on}} [[catenary]] arch to be placed on the banks of the [[Mississippi River]]. However, these plans were modified over the next 15 years, placing the arch on higher ground and adding {{convert|40|ft|m|0}} in height and width.

The central architectural feature at the base of the arch is the [[Old Courthouse (St. Louis, Missouri)|Old Courthouse]], which was once the tallest building in Missouri and has a dome similar to the [[United States Capitol]] and was placed on the building during the [[American Civil War]] at the same time as that on the U.S. Capitol.

Saarinen developed the shape with the help of architectural engineer [[Hannskarl Bandel]]. It is not a pure inverted [[catenary]]. Saarinen preferred a shape that was slightly elongated and thinner towards the top, a shape that produces a subtle soaring effect, and transfers more of the structure's weight downward rather than outward at the base.

When Saarinen won the competition, the official notification was sent to "E. Saarinen", thinking it to be the architect's father [[Eliel Saarinen]], who had also submitted an entry. The family celebrated with a bottle of champagne, and two hours later an embarrassed official called to say the winner was, in fact, the younger Saarinen. The elder Saarinen then broke out a second bottle of champagne to celebrate his son's success.

Among the five finalists was local St. Louis architect [[Harris Armstrong]].