What is "on the level streets of turn of " ?

Dear Sirs :
Could you please tell me the meaning of "on the level streets of turn of" ? Below is the entire sentence.

For it was on the level streets of turn of the century Chicago that Frank Lloyd Wright got his start.

Thank you so much

Jason Chao

God Bless!

I think we should consider the words "at the turn of the century" together.

"at the turn of the century" means in or around the year 1900 for example or any other century which is considered by the author.

Thanks!

And Chicago is set on flat land, so its streets do not go up and down hills, so they are "level streets".