The coal railways had been planned in an era when level routes were required for horse haulage .
The line through Coatbridge was south to north , reaching Glasgow , in the case of the Garnkirk line , by a wide northward sweep .
The coal railways had been planned in an era when level routes were required for horse haulage , and the line through Coatbridge was south to north , reaching Glasgow , in the case of the Garnkirk line , by a wide northward sweep .