Today in History
What went down and why you should care.
jul 07 Learn More Construction on the Hoover Dam Begins
![](https://media1.shmoop.com/images/general/calendar-may-dec/calendar-of-the-day_0183_jul7-hoover-dam-begins.jpg)
Construction on the Hoover Dam began on this day in 1930. It was the first building site where hard hats were required. Before that, if a worker wanted to protect his noggin, he'd cover his hat with tar and let it harden. Sounds safe.
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