Table A-1: Reporting Marks Used
| Marks |
Railroad Name |
| AAR | A.A. Rust Lumber Co |
| ATSF | Atchison, Topeka & Santa Fe |
| B&D | Baltimore & Delta RR |
| B&BL | Burns & Biggs Lumber Co. |
| B&LH | Baltimore & Lehigh |
| B&L | Boca & Loyalton |
| BC&F | Boston Coal & Fuel Co. |
| BIW | Brewton Iron Works |
| BJY | Booker Junkyard |
| BLCO | Banner Lumber Co. |
| BLC | Biggs Lumber Co. |
| BMLC | Blacksoler-Miller Lumber Co. |
| C&NW | Carolina & Northwestern RR |
| C&SE | Colorado & Southeastern RR |
| C&SL | Cairo & St. Louis RR |
| C&SW | Colorado & Southwestern RR |
| C&S | Colorado & Southern |
| C&TS | Cumbres & Toltec Scenic Railway |
| CADA | Compania Azucarera de Altamaria (Cuba) |
| CC&CS | Cripple Creek & Colorado Springs |
| CdeP | Cerro de Pasco Copper Co. (Peru) |
| CFC | Calumet Fuel Co. |
| CNTP | Cincinnati, New Orleans & Texas Pacific |
| CO&NW | Colorado & North-Western |
| CRM | Colorado Railroad Museum |
| CSC | Columbia Steel Corp. |
| CK | Colorado-Kansas RR |
| CR | Crystal River |
| CS | Cincinnati Southern |
| CV | Connotton Valley |
| CVR | Castle Valley Railroad |
| D&RG RC | Denver & Rio Grande Railroad Consolidated |
| D&RG RR | Denver & Rio Grande Railroad |
| D&RG Ry | Denver & Rio Grande Railway |
| D&S | Durango & Silverton Narrow Gauge Railroad |
| D&SL RR | Denver & Salt Lake Railroad |
| D&SL Ry | Denver & Salt Lake Railway |
| DB&W | Denver, Boulder & Western RR |
| DCMC | Detroit Copper Mining Co. |
| DL&G | Denver, Leadville & Gunnison |
| DNW&P | Denver, North-Western & Pacific RR |
| DRGW RO | Denver & Rio Grande Western Railroad Reorganized |
| DRGW RR | Denver & Rio Grande Western Railroad |
| DRGW Ry | Denver & Rio Grande Western Railway |
| DSP&P | Denver, South Park & Pacific RR |
| DC | Deep Creek RR |
| EBT | East Broad Top RR & Coal Co. |
| EN | Eureka-Nevada |
| F&A | Franklin & Abbeville |
| F&CC | Florence & Cripple Creek |
| FL&C | Fitzhugh, Luther & Co. |
| GCLC | George Cousin Lumber Co. |
| GF&C | Great Falls & Canada |
| GJ&S | Gainesville, Jefferson & Southern |
| GMD&S | George M. Dilley & Son |
| GT&C | Ghost Town & Calico RR (Knotts Berry Farm) |
| GM | Gainesville Midland |
| H&HL | Hallack & Howard Lumber Co. |
| HMC | Hyman-Michaels Co. |
| HRRC | Heritage RR Co. |
| IV | Indian Valley RR (California) |
| K&E | Kentwood & Eastern Rwy |
| L&HC | List & Hallett Co. |
| LCC | List Construction Co. |
| LL&E | Lindsay Lumber & Export Co. |
| LLC | Livingston Lumber Co. |
| LMC | Lester Mill Co. |
| M&G | Mathew & Geist |
| MBMC | Morse Bros. Mining & Supply Co. |
| MTS | Montana Southern Rwy |
| MLC | Montezuma Lumber Co. |
| MM | Magic Mountain RR (Colorado) |
| MS | Morenci Southern RR |
| MT | Midland Terminal RR |
| NCNG | Nevada County Narrow Gauge |
| NGM | Narrow Gauge Motel |
| NLC | Natalbany Lumber Co. RR |
| NMLC | New Mexico Lumber Co. |
| NRR | Nacozari RR |
| NSRR | North Shore RR (California) |
| NWP | Northwestern Pacific RR |
| PLC | Pagosa Lumber Co. |
| PPC | Pacific Portland Cement |
| PS&R | Pueblo Smelting & Refining Co. |
| PSW | Pueblo Steel Works |
| RCL | Red Cypress Lumber RR |
| RG&PS | Rio Grande & Pagosa Springs Railroad |
| RG&SF | Rio Grande & Santa Fé |
| RG&SW | Rio Grande & Southwestern |
| RGP&N | Rio Grande, Pagosa & Northern Railroad |
| RGP&S | Rio Grande, Pueblo & Southern |
| RGSdeC | Rio Grande, Sangre de Cristo |
| RGG | Rio Grande Gunnison Railway |
| RGJ | Rio Grande Junction Railway |
| RGS | Rio Grande Southern Railroad |
| RGW | Rio Grande Western |
| RG | Rio Grande Railroad |
| RL&L | Robinson Land & Lumber Co. |
| SA | Steven Arnold |
| SCD&P | Silver City, Deming & Pacific RR |
| SCC | Spring Canyon Coal Co. |
| SFS | Santa Fe Southern RR |
| SG&N | Silverton, Gladstone & Northerly RR |
| SI&E | Southern Iron & Equipment Co. |
| SLVS | San Luis Valley Southern RR |
| SLS | San Luis Southern |
| SML | Scrap Materials, Ltd. & Learner Co. |
| SNL | Sayre, Newton Lumber Co. |
| SNR | Silverton Northern RR |
| SP | Southern Pacific Transportation Co. |
| SPV | San Pete Valley |
| SRR | Silverton Railroad |
| SSLV | Southern San Luis Valley RR |
| SV | Sumpter Valley RR |
| TV | Tuscarora Valley RR |
| U | Uintah Rwy |
| UC RR | Utah Central Railroad |
| UC Ry | Utah Central Railway |
| USS | U.S. Steel Corp., Geneva Steel Div. |
| UTAH | Utah Railroad |
| VAFC | Victor American Fuel Co. |
| WCL | Walker Co. Lumber RR |
| WPY | White Pass & Yukon |
| WC | Woodmoor Corp. |
| WP | Western Pacific Rwy |