Good Question! How Mt. Oliver Borough Eluded City Of Pittsburgh Annexation By Katie Blackley • Mar 13, 2017 Megan Harris / 90.5 WESA Listen Listening... / 6:12 Why are there two separate Mt. Oliver's south of Pittsburgh? 90.5 WESA's Good Question explores how the borough evaded annexation by the city and why they aren't looking to change that any time soon. It was the best of times, it was the worst of times. It was the age of steel, it was the age of annexation. On any Pittsburgh city map, there is an unlabeled stretch of land between the neighborhoods of Mt. Oliver and Knoxville.