Augusta Raurica is a Roman archaeological site and an open-air museum in Switzerland located on the south bank of the
Rhine 
river about 20 km east of
Basel 
near the villages of
Augst 
and
Kaiseraugst 
. It is the site of the oldest known Roman colony on the Rhine.
Founding
Augusta Raurica, or Colonia Augusta Rauracorum, was founded by Lucius Munatius Plancus around 44 BC in the vicinity of a local Gallic tribe, the Rauraci, relatives of the Helvetii. No archaeological evidence from this period has yet been found, leading to the conclusion that, either the settlement of the colony was disturbed by the civil war following the death of Julius Caesar, or that Plancus' colony was actually in the area of modern Basel, not Augst.
Successful colonization of the site had to wait for Augustus' conquest of the central
Alps 
around 15 BC. The oldest find to date at Augusta Raurica has been dated to 6 BC by dendrochronology.
Name
The inscription on Munatius Plancus' grave merely states the name of the colony as Colonia Raurica.