Öz Is Vitruvius’ description of the city of Halikarnassos 2.8.10-15 based exclusively on other written evidence or was he actually there to see it himself? It would, of course, greatly enhance the value and importance of the Information he gives, if one could be sure that he did not merely quote from an other source without ever having had the opportunity of checking written evidence through a personal visit to Halikarnassos. The question to vvhich extent, irrespective of its true authorship, the passage may be considered plausible and trustworthy will be dealt with in the forthcoming volüme 2 on written sources of the Halikarnassos Publication. The objective of the present paper is to discuss the problem whether Vitruvius occupation as a military engineer in the service of Caesar and Augustus is likely to have provided obvious opportunities for him to visit Halikarnassos.