Each historic construction project contains its own intricate story, from the massive projects of the ancient world to modern era American masterpieces like the Golden Gate Bridge, Hoover Dam, and Mount Rushmore. Although on the surface they are bold statements about the abilities of those who turned them from a sketch into reality, each project also offers a learning opportunity for contemporary engineers and construction companies looking to follow in their footsteps. Here’s a look at some of the stunning facts and amazing stories behind some of the country’s most iconic construction projects.

Golden Gate Bridge:

When chief engineer Joseph Strauss introduced his initial plans for the Golden Gate Bridge in 1921, the cantilever/suspension bridge combination was widely panned and one critic even went as far as to call it an “upside-down rat trap.” Putting aside his pride, Strauss would then invite some of his biggest rivals onto the project in an effort to find something a little more eye-appealing, ultimately leading to the Art Deco-dominated suspension design that would become one of the most famous bridges in the world. Strauss’ initial plan would give way to input by a handful of experts, including Manhattan Bridge engineer Leon Moisseiff, and the team made the calculations by hand over the course of the next decade before the bridge was actually started.

But even though the collaborative effort turned out to be an enormous success, further complications turned up in the mid-1930s when the U.S. Navy became concerned about visibility and the possibility of ships being trapped in San Francisco Bay. The Navy’s answer was to recommend painting yellow and black stripes onto the bridge, although later on Navy engineers suggested that a candy cane look of red and white stripes would be sufficient. After lengthy discussions, the striped approach was finally scrapped and the now-famous “international orange” was used, although the color was originally only supposed to be a primer. In the end, the bridge was built between 1933 and 1937, utilized more than 165 million pounds of steel, and even required locals to put up farms and houses as collateral to pull together $35 million in bonds to cover construction costs.

Hoover Dam:

The Hoover Dam, or Boulder Dam as it was originally called, would turn out to be one of the greatest engineering feats of the 20th century. Looking to control flooding of the Colorado River and provide hydroelectric power, the dam was started by Six Companies, Inc. in 1931 and brought enormous engineering challenges, as a concrete structure of its size and scope had never previously been attempted. Battling the rigors of summer and difficult overall working conditions, the project brought together more than four million cubic yards of concrete in total, which is actually enough to build a road from one side of the continental U.S. to the other.

Handling this amount of concrete in the extreme heat also brought considerable challenges, which is why a super-refrigerator had to be built to produce as much as a thousand tons of ice in a day in order to keep it cool. Despite periods of record-breaking drought and a plethora of practical problems, the dam was even brought in two years ahead of schedule, further cementing its reputation as one of the greatest American construction projects in history. Ultimately, the 726-foot high dam would become the tallest dam in the world when it was finished in 1936, a distinction it held until Switzerland’s 820-foot high Mauvosin Dam was completed in 1957. Today, Hoover Dam draws in about seven million tourists a year and powers more than a million homes throughout Arizona, Nevada, and California.

Fun fact: President Franklyn Roosevelt didn’t invite namesake Herbert Hoover to the dedication of the dam and infamously snubbed his predecessor during his dedication speech. The dam wasn’t officially called Hoover Dam until 1947.

Mount Rushmore:

After much deliberation throughout the mid-1920s, state and federal lawmakers fully signed on to begin Mount Rushmore in 1927, with the goal of creating a grand monument to four of the nation’s most iconic presidents. Following a commission to work on a monument on Stone Mountain in Georgia, sculptor Gutzon Borglum chose the specific spot in the Black Hills of Keystone, South Dakota thanks to its high perch and easy visibility from the areas down below. But even though location proved to be nearly perfect, Borglum and his team of sculptors weren’t immune to missteps. Originally set to appear to George Washington’s right, the Thomas Jefferson sculpture failed to meet Borglum’s expectations and had to be blown up and moved after 18 months of work.

Utilizing precisely placed dynamite, more than 90% of the faces of Rushmore was actually completed by cutting edge explosive techniques, which was a precarious and time-consuming process. Despite the danger, however, not a single worker was lost throughout the 14-year project and it was finally completed in 1941. Unfortunately for Borglum, he died of complications from surgery mere months before it was fully completed and dedicated, although his son, Lincoln, was able to fill-in to help finalize the project. Even though funding limitations caused Borglum to abandon the original plan to depict Washington, Jefferson, (Teddy) Roosevelt and Lincoln all the way to their waist, Mount Rushmore would quickly become a national emblem and the driving factor of tourism in South Dakota.