Boulder City in Clark County, Nevada — The American Mountains (Southwest)
For the Record
Photographed by Sandra Hughes Tidwell, September 9, 2025
1. For the Record Marker
The Mike O'Callaghan-Pat Tillman Memorial Bridge boasts the longest concrete arch in North America. It is the biggest composite (steel and concrete) bridge in the Western Hemisphere, and the highest concrete-arch bridge in the world.
Most expensive
The San Francisco-Oakland Bay Bridge was damaged in the 1989 Loma Prieta earthquake. Its eastern span was repaired, but the western span had to be replaced at a cost of $6.3 billion, making it the most expensive bridge ever built. At a mere $240 million, the Memorial Bridge project was a bargain!
Tallest
The tallest bridge in the world is the Millau Viaduct in southern France. "Tallest" refers to the height of the structure itself, from the lowest visible part of the structure to its high point. The designers of the Memorial Bridge made a conscious decision not to build a cable-stayed structure like the Millau Viaduct to avoid visual intrusions on the skyline.
Longest Concrete Arch
The Belpanjiang Qinglong Bridge in China has the longest concrete arch span in the world at 1,460 feet (445 meters). The span of the concrete arch of the Memorial Bridge is 1,059 feet (323 meters), making it the tenth longest.
Highest
The Sidu River Bridge in western China is the highest bridge in the world at 1,627 feet (496 meters). The height of a bridge is the distance from the bridge deck on which traffic moves to the ground (or water) beneath. The Memorial Bridge is 890 feet (271 meters) high.
The Royal Gorge Bridge in Colorado, the highest bridge in the world until 2001, is the only bridge in the United States that is higher than the Memorial Bridge. ut us tge 12tg gugest ub tge wirkd at 955 feet (291 neters) above the Arkansas River. The Memorial Bridge ranks 14th globally.
Topics. This historical marker is listed in this topic list: Bridges
this page online
Location. 36° 0.906′ N, 114° 44.692′ W. Marker is in Boulder City, Nevada, in Clark County. It is on Hoover Dam Access Road. This marker is next to the step-by-step marker. Touch for map. Marker is at or near this postal address: 81 Hoover Dam Access Road, Boulder City NV 89005, United States of America. Touch for directions.
Regionally, this marker is in Nevada’s Colorado River Valley, in the Mojave Desert, and in Greater Las Vegas. It is also in the American Southwest and in the Mountain West. Globally, it is in North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it finds itself in what was once New Spain and also Mexicos Alta California.
Other nearby markers. At least 8 other markers are within walking distance of this marker: Worthy of the Neighborhood (here, next to this marker); Discover Hoover Dam (here, next to this marker); Step by Step (here, next to this marker); Breaking the Bottle Neck (here, next to this marker); Design Decisions (a few steps from this marker); Get Good Footing with Anchors & Foundations (a few steps from this marker); Find Solid Ground with Surveys & Tests (a few steps from this marker); America's Finest (within shouting distance of this marker). Touch for a list and map of all markers in Boulder City.
Credits. This page was last revised on October 2, 2025. It was originally submitted on September 27, 2025, by Sandra Hughes Tidwell of Killen, Alabama, USA. This page has been viewed 81 times since then and 18 times this year. Photo 1. submitted on September 27, 2025, by Sandra Hughes Tidwell of Killen, Alabama, USA. • Andrew Ruppenstein was the editor who published this page.
