Ancient Rome: The Seven Hills

Directions: 
Grammatically correct the sentence(s) below, in red.  There are many missing commas and a needed use of the colon ( : ). 

Ancient Rome was fortunate to have agreeable geographical protections from potential enemies the Alps protected Rome from northern invaders and there were seven hills around Rome Aventine Caelian Capitoline Esquiline Palatine Quirinal Viminal. 

Great Five Minute Video introduction to Rome.

Suggested Answer:
Ancient Rome was fortunate to have agreeable geographical protections from potential enemies. The Alps protected Rome from northern invaders, and there were seven hills around Rome: Aventine, Caelian, Capitoline, Esquiline, Palatine, Quirinal, Viminal.