Conoco Oil Company Gas Station Road Maps of Colorado
Conoco Oil Company - Colorado Road Maps
Collectable Conoco Gas Oil Station Road Maps
Pictures of Old Vintage Conoco Gas Service Station Road Maps
Conoco Oil Company - Colorado Road Maps - Prewar Front
Conoco Oil Company - Colorado Road Maps - Prewar Back
Conoco Oil Company - Colorado Road Maps - Postwar Front
Conoco Oil Company - Colorado Road Maps - Postwar Back
Conoco Oil Company - Colorado Road Maps - 1964+ Front
Conoco Oil Company - Colorado Road Maps - 1964+ Back
I believe there is not map dated 1951, but one of the maps form adjacent years could have been published in 1951. There are two versions of the 1970 map, one is pictured in the 60 slot above. I believe the 1980 Conoco Colorado maps exists, I do not have a copy, so I inserted an Oklahoma Conoco map in the slot.
The following clickable link will open a Check-List type Spreadsheet that will include Map Codes, Copyright Dates and other descriptive information for the above pictured map series. Conoco-Colorado-Spreadsheet