Railroad Archives Online
- CollectionD0027 - Timothy Miller Collection
- Series004 - Northern Pacific Railroad Company
- Subseries Level 1009 - Engineering Records
- Subseries Level 2008 - Physical plant drawing
- Subseries Level 3003 - Maintenance Facilities
- 828 more...
- ItemStruc006951 - Northern Pacific Engineering Drawing, Sand Facilities at Helena, Montana, 1953
- ItemStruc006952 - Northern Pacific Engineering Drawing, Sand Facilities at Helena, Montana, 1957
- ItemStruc006953 - Northern Pacific Engineering Drawing, Sand Facilities at Helena, Montana, 1957
- ItemStruc006967 - Northern Pacific Engineering Drawing, Unnamed Structure at Helena, Montana, 1969
- ItemStruc006968 - Northern Pacific Engineering Drawing, Unnamed Structure at Helena, Montana, 1956
- ItemStruc006969 - Northern Pacific Engineering Drawing, Unnamed Structure at Helena, Montana, 1969
- ItemStruc006970 - Northern Pacific Engineering Drawing, Unnamed Structure at Helena, Montana, 1964
- ItemStruc006971 - Northern Pacific Engineering Drawing, Unnamed Structure at Helena, Montana, 1960
- ItemStruc006973 - Northern Pacific Engineering Drawing, Unnamed Structure at Helena, Montana, 1950
- 474 more...