I make several trips a year to various parts of Italy.   While I haven't tried every Italian and Pizza place in St. Louis, I have tried all of the well-known locations on 'the hill'.  Erio's in St. Peters is by far the best and most authentic.  The service is impeccable, and the prices are extremely reasonable.  Do yourself a favor and give it a try...you won't be disappointed.
Pros:  Service, Quality, Quantity, parking
Cons:  Location, not much space
                        
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