Blue grapes

I don’t know what this grape variety is called. But it is very tasty. Sweet with sourness. And wasps don't eat it. Almost all bunches of grapes are intact. It usually ripens in mid-September. One thing is bad. These grapes grow in an abandoned neighbor's house. On the very border with my piece of land :) But..I manage to eat a little of these grapes without violating the boundaries of other people's property.