Tribes and cities in Gaul at the time of Julius Caesar. Data for this map were retrieved from a map out of the book "Julius Caesar" written by Philip Freeman (ISBN 978-1-906217-69-3).
Legend:     

━━━  Primary lines
━━━  Secondary lines
━━━  Tertiary lines
http://sharemap.org/runnerup/France
Geospatial data sources: 

Open Street Map Data (ODbL) - http://www.openstreetmap.org/copyright
NORTAD - http://www.bts.gov/publications/north_american_transportation_atlas_data/
Natural Earth - http://www.naturalearthdata.com/
Citypeek