We have been going to Antica Osteria del Porto for many years, and typically whenever we go out on a Monday evening it is our destination as most restaurants we like in the Lugano area are closed on Mondays.
The location by the river and lake is nice and it is quite beautiful to eat outside under the trees. Service is pretty good and the food is good. I always like their very tasty risotto luganiga e merlot, but they have other good ones too. It is not an excellent restaurant, but it's good and I recommend it.