This is a two piece sculpture installed on buildings across the street from each other – one in Garfield, the other in Bloomfield.
We were able to find very little information on it. Only that it was a project of the Penn Avenue Arts Initiative, and this paragraph in the Post Gazette Arts and Entertainment section by Bob Batz Jr in June of 2002:
"The Gateway" is two large mirror-image stainless steel sculptures mounted on the outside walls of two buildings on either side of Penn Avenue (5149 and 5150) symbolizing a bridge between Friendship, Bloomfield and Garfield. The Penn Avenue Arts Initiative collaborated on it with artists Michael Walsh and Jeremy Groznik.