Building a city is complicated and, even with a huge amount of manpower, building materials need time to cure and set once used.
The Colosseum of Rome took at least eight years to build, but the Romans could build much faster when they wanted to. Julius Caesar’s first bridge over the Rhine in Germany, was built in just 10 days using 40,000 legionaries.
It’s doubtful that 10 times as many men could have done it in a day though, and building a city is much more complicated. Many Roman residential buildings were six stories high, and you can’t build the top floor before the one below is complete.
Cement needs more than a day to set and delivering all the materials for every building at once would be impossible along narrow Roman streets.
Read more:
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- Why aren’t large Lego bricks used to build full-size buildings?
- Can we recycle concrete?
Asked by: Yousef Medina, Rome
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