The Pacific Ring of Fire is a zone of major volcanic activity because of tectonic plate boundaries. Where is another area of Earth where you might expect to find such volcanic activity?
the mountains of Italy where two plates, The european and African plates collide.
The ocean crust that is connected to the African plate is being pushed under the European Plate. Where the ocean crust is pushed under the continental crust the material of the crust is melted. This magma built up under the continental crust creates pressure resulting in volcanic activity.
The famous Vesuvius volcano that destroyed and persevered Pompeii was a result of this plate boundary. Presently there is an active volcano in Etna Scilly that is a result of this plate boundary.
It is likely that the Alps are a result of the collision between these plate boundaries.