· No building in DC may be taller than 13 floors so that no matter where in the city you are, you can see the monument to our first President, Washington.
· Hard Hats were first invented specifically for workers on the Hoover Dam back in 1933.
· The Great Pyramid at Giza, Egypt, constructed around 2500 BC, was the tallest building in the world until the Eiffel Tower was erected in 1889.
· San Francisco’s Golden Gate Bridge took 25 million man-hours to build.
· Bricks are the oldest manufactured building material still in use. Egyptians used them 7,000 years ago.
· Built in only 16 months , the Pentagon is only 71ft tall and yet it has 5 floors, 17.5 miles of corridors, 131 stairways, 284 restrooms, 691 drinking fountains, and 7,754 windows.