Why do you think manholes are round in shape?

(You need to think a little crooked for this )

Actually the original answer is not correct. If the cover was a perfect square, it would not be able to fall through in any way. There are two reason why the cover is a circle. The first is because a circle will form the most snug fit. It can be twisted to make sure it is truly snug...no other shape could do this. The second reason is because a circle can be rolled. So when workers open the manhole up, they do not need to completely lift up the cover, just roll it out of the way.

Posted by rpm on 2003-03-11 18:47:28