I currently live right on the border of Oh and PA. Prior to that I lived in Penna. all my life (30+ years), spending the last decade or so of that in the city of Pittsburgh.
'Highland Park' is/was an upscale residential community in Pittsburgh's East End. The whole EE area has gone downhill since the 1960s. While Highland Park itself is a decent area for the most part it is surrounded and near some
REALLY scuzzy places (E. Liberty, Oakland, Wilkinsburg, etc.). If you don't ( why not??

) have it already get your PA CHL and carry. Those PA concealed carry laws are much more liberal than our Ohio ones.
The Pittsburgh Zoo is in Highland park, and there are some of the best cultural attractions in Pittsburgh nearby.
One thing when apartment shopping in Pgh.'s east end is to be
very careful your landlord isn't saying it is a 'Highland Park' address when it is really another neighborhood that should command less rent and more ammo.
Its really not all that bad there but beware your (as much as everywhere else) surroundings