Answer: The road, crucifix/cross, sidewalks, railroads, and so much more.
Step-by-step explanation: Roads are parallel so that everyone can get to the same place in different lanes. This is important because lines that aren't parallel will inevitably meet, meaning that a highway would eventually merge its two lanes. This happens, but most of the highway is parallel. The same is true of sidewalks and railroads. The crucifix/cross is a Christian symbol, and while I'm not Christian, I'm sure it's important to a lot of people who are.
the rail road helps the train stay where its supposed to go and the cross walk helps cars not hit people walking down the sidewalk and the streets help drivers drive smother and help them get more gass mileage