Nothing is easier than to step over the frontier between great nations.
"The Expositor's Bible: The Book of Exodus"
G. A. Chadwick
As we crossed the frontier a difference in the dress of the common people was at once obvious.
"Due North or Glimpses of Scandinavia and Russia"
Maturin M. Ballou
England has always a frontier war or two on her hands, and I got into one.
"The Locusts' Years"
Mary Helen Fee