Is there a service showing all direct directions from a given city?

Question

API

What I want: I want to enter the name of the city and get a list of all destinations. For example, the query "St. Petersburg" should, accordingly, return a list of all cities connected with St. Petersburg by direct air connection. And the query "St. Petersburg - Italy" showed all the cities of Italy associated with St. Petersburg. It would be great if the service also showed the dates.
Why is this needed? I would like, for example, to drive around the cities of Italy, but not particularly overpay, and which city to fly to does not play a special role. And where to fly from (Tallinn, Helsinki, Riga or from St. Petersburg itself) is also not particularly important.
On aviasales and the like, I did not find such an opportunity.

Answer 1

airtraffic.eu

Answer 2

Google knows how

Answer 3

Something like this?