Zane Grey 
U. P. Trail [PDF ebook] 

Although Western writer Zane Grey is best remembered for The Riders of the Purple Sage, the novel The U.P. Trail is a favorite among critics and fans alike. This ambitious tale weaves a grand narrative of the construction of the Union Pacific Railroad line, which serves as the backdrop for a tender romance that blooms between the virtuous Allie and the mysterious and taciturn protagonist, Warren Neale.