Kennywood is a mix of the old and new. You'll get some of the coolest modern rides and then get to ride things from the early 1900's. They also have some cool theme rides (haunted house, Exterminator).
The Phantom's Revenge and Sky Rocket were amazing. They were completely smooth, yet thrilling rides.
The park is landscaped very well and many lines are under the shade of the trees, so you're not waiting while the sun beats down on you.
When first pulling into the park (free parking) you get a fair-like feeling....but upon entering you'll see it's a full-fledged park. Then, travel through a magical tunnel to a world of fun.
Riding things that were there for almost 100 years is kind of special.
I definitely recommend Kennywood.
More than a few rides were out of order or just not running the day we went. Many people smoked in non-designated areas.