Street by Building
Barry runs into the alley and rescues Iris who is falling from the building in episode 2x03 “Family of Rogues”.
Kid Flash vs. The Rival
Barry runs up and sees Kid Flash chasing around The Rival in episode 3x01 “Flashpoint”.
Barry is tagging along with Julian's investigation into the monster attack when the monster appears again and he has to save Julian from another transformer explosion in episode 3x05 “Monster”.