The first zoo in the United States sits on a large area of land right in a large city. It's as if someone cleared out a bunch of rowhomes and urban streets and plunked a zoo down in the center. The area where the zoo is located is not the best area of Philadelphia, although it's not considered dangerous.
The Philadelphia Zoo is rather small as zoos go, but that's because so much city was built up around it. Parking is difficult, especially on days when the zoo is crowded. There is one very small parking lot near the entrance. It fills quickly. If you don't get that one, there is a larger lot up the street that requires a short walk to the entrance. You can also park on the street that surrounds the zoo. If you are not a member, parking is a staggering $12 even if you park on the street.
Once you get inside things change. Philadelphia has an older zoo, it's true, but it's a lovely zoo. You are greeted by a sweet statue of an elephant mom and baby. A little bit further is a large fountain featuring antelopes leaping through the water. (The lion statue outside the zoo's entrance is another story. It may be realistic but it's sad and definitely does not convey fun). Peacocks roam the grounds, and a nice lake decorates the center.
Philadelphia knows what it can and cannot do with its zoo, and I am glad for that. They recently created a wonderful area for their big cats. (No, you will no longer see the stone semi-circle made famous by Rocky Balboa). They also shipped off their elephants to wildlife centers because they realized they coul dnot give them the kind of habitat that would be healthy for them.
My only issue with the zoo is the way they nickel-and-dime you. Between pony rides and camel rides and balloon rides you can spend a fortune. Also they only offer junk food, and it is very expensive.