Growing in popularity and availability, these true Berries are about the only edible fruit made by plants in the Rhododendron and Heath Family (the Ericaceae). Cooks will look for them in the same area as they expect Strawberries, Blackberries, and the other berry imposters. In that company, the Ericaceous fruit are the only real Berries (or Bacca).
The Systematist would look for Blueberries and Cranberries somewhere in the vicinity of Tea and Kiwi, which are in related families.