A high way would be a great route
Epidemic: an outbreak of disease that spreads quickly and affects many individuals at the same time : an outbreak of epidemic disease
Pandemic: occurring over a wide geographic area and affecting an exceptionally high proportion of the population
(an example is the coronavirus)
I think the context of this was that the Roman Empire started off pretty small but expanded greatly in the about 400 years the map shows
Answer: financial problems and educational opportunities