These locations are within very high human population areas. Pittsburgh has many areas with steep cliffs and ravines which aren't very easily adaptable to use by humans, hence many little islands of wilderness within the county.
Pittsburgh has also been home to a couple Peregrine Falcons for over a decade which nest on the towering buildings right in downtown Pittsburgh, which have spread to many other local areas.
Pittsburgh has also been home to a couple Peregrine Falcons for over a decade which nest on the towering buildings right in downtown Pittsburgh, which have spread to many other local areas.

When a pair of bald eagles wove a 5-foot nest of sticks on an isolated hillside in suburban Allegheny County in 2010, it was seen as a sort of environmental milestone -- nature's confirmation that the Pittsburgh region had cleaned up its act.
But the new eagles in town -- two nesting pairs that
have taken up residence in sight of high-traffic corridors in Harmar and Hays -- are avian rock stars. Their nesting rituals have been witnessed daily by crowds of fans at viewing sites that have become Allegheny County's newest tourist attractions.
And as local bird-watchers learn the rules of eagle etiquette, Pennsylvania's growing bald eagle population is perhaps within months of being removed from the state's threatened species list.
"Did you ever think you'd live long enough to see three bald eagle nests in Allegheny County?" said Tom Fazi, southwest region education officer for the state Game Commission.
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