This reference work meticulously documents the year-by-year construction and abandonment of railroad trackage in Colorado from 1867 to 1964. It details the building of not only main lines but also industrial sidings, providing essential data for each entry including railroad name, location, track mileage, gauge, and a brief description. The chronological arrangement offers a clear view of the state's railroad development, highlighting the pace of construction and contraction over time. The book is richly illustrated with 250 black and white photographs and several maps, supported by notes and a bibliography.

This comprehensive reference work is designed for historians, rail enthusiasts, and researchers interested in Colorado's transportation history. The chronological format and detailed entries provide a valuable resource for understanding the state's railway development. The inclusion of numerous photographs and maps enhances its utility as a historical document. Its detailed approach suggests it serves as a definitive resource for its specific subject matter.