| Subject/Photo | Publication | Page |
| U S Leasing XM-32B/C/D box car Cascade green | BB 7 | 18 |
| U23C #463 experimental green/white scheme (10/69) | BB35 | 130 |
| U23C green/white transitional scheme (7/69) | BB35 | 99+ |
| U25B #100 with NYC/PC pool (10/68) | C 98 | 4 |
| U25B #100, 101, 102, 104 eastern Colorado train #63 | C 02 | 8+ |
| U25B #2537 NYC pool Elkhart-Cicero (c1968) | C 92 | 6 |
| U25B #2560 NYC in CB&Q/NYC/PC pool (10/68) | C 98 | 4 |
| U25C #550 & #555 & #558 Henry, Ne. | BB31 | 32+ |
| U25C #556 & #557 & #559 Antioch (11/65) | BB 9 | 11 |
| U25C #556 overhead view Burlington Shops | BB26 | 77 |
| U25C #556, 557 stock train #80 (11/65) | BB25 | 1+ |
| U28C #564 Barr, Co. (9/66) | C 90 | 16 |
| U28C #570 & 6 others diesels Wind River Canyon (9/68) | C 00 | 24 |
| U28C #572 Wind River Canyon (6/67) | C 01 | 12+ |
| U28C #574 Broken Bow, Ne. (10/66) | BB25 | 124 |
| U30B #142, 146 pool, New York Central (c1968) | C 92 | 6 |
| U30B #151 sugar beet train (1/70) | BB32 | 44+ |
| U30B #154 (1968) | C 98 | 14+ |
| Under Crossings Clearance Warning sign | DS10 | 64 |
| Underbody details baggage class BA-19/19A | BB36 | 56-7 |
| Underpass Everywhere West sign, Broadway, Aurora | BB46 | 64 |
| Underpass rebuilding | Z 50 | 16+ |
| Underpass rebuilding Interstate #294 Hinsdale, Il | Z 51 | 12+ |
| Union Electric plant Portage des Sioux (1966) | BB35 | 97 |
| Union Pacific loco #836 and Zephyr unit Omaha (10/50) | C 95 | 18 |
| Union Pacific pool cabooses silver paint | Z 35 | 13 |
| Union Pacific pool power, Chicago-Grand Island (3/61) | C 94 | 12+ |
| Union Pacific pooled power (Z Q&A 94-11, Z 30) | Z 30 | |
| Union Refrigerator billboard reefer examples | BB28 | 4 |
| Union Refrigerator Transit Co. billboard reefer | BB28 | 20 |
| Union Switch & Signal Car Retarder System panel | Z 36 | 24 |
| Union Switch & Signal CTC board Red Oak, and operator | RO | 7 |
| Unit train hoppers class HT-11 Shawnee Steam (1964) | BB35 | 94 |
| Unit train hoppers class HT-12 (1966) | BB35 | 96-7 |
| Unit trucks 100,000th box car #37000 (XM-32) (7/48) | BB 7 | 12 |
| Unit trucks 100,000th box car (#37000) (7/48) | Z 38 | 8+ |
| United States Envelope Co. drinking cups for Zephyr advert (4/34) | BB43 | 36 |
| United States Rubber Co. rubber supplies for Zephyr advert (4/34) | BB43 | 26-7 |
| United States Steel Corp stainless steel for Zephyr advert (4/34) | BB43 | 40-1 |
| Unusual structures Coalfields | BB35 | 198-9 |
| UP & PRR & Q pool train #63 Denver (3/68) | C 02 | 24+ |
| U.S. Mail Transfer Depot, Council Bluffs (c1910) | BB45 | 19 |
| USRA composite gondolas (GA-15) BP (1/19) | DS 7 | 3 |
| USRA double sheathed box car (XM-24) history | DS 4 | 1 |
| Utah Idaho Central bus (as Burl. Trailways) (10/50) | BB24 | 45 |