Whenever l go to great structures, l am usually astounded at the time, effort, and skill that had been used to build them, and how impressive they are. I wouldn't know where to start on such large projects (apart from delegating all of the work).
The Hoover Dam, between Arizona and Nevada, is a fine example. The construction of it, even more so. When there, standing at (or on) the edge, it is mightily impressive, and well worth the trip out to see it it if you are in Las Vegas (hire a car).
It was built in the mid 1930's and previously known as The Boulder Dam, drawing it's water from The Colorado river, forming Lake Mead, and like anything high up, it draws you to the edge, or at least it does to me (as did The Grand Canyon).
About 100 people lost their lives working on the dam, and l wouldn't be taking a wild guess that they would have been the poor old labourers, working for peanuts (whether they were allergic to them or not), who, during the depression (when it was built), Health and Safety regulations would have been pretty slack, or non existent as far as they were concerned.
Still mightily impressive, and an excuse to feature this song.
Sugar - Hoover Dam.