A local favorite: beginners like it for its relatively easy (mostly Class II, but there are a couple of III-) rapids; experienced paddlers head there for the play. Everyone likes its beauty.
Check out
Three Rivers Paddling Club or
Larry Wentzel's exhaustive description.
Directions: head for McConnell's Mill State Park. From the West and North, take I-80 to Rt. 19 South. Check out the Keel-haulers Map (linked to in the 'Maps' section at the right) for details to the putin and takeout. There are several alternate putins: the Ranger Station, probably half a mile downstream from Rt. 422; Frew's Mill, a mile or so upstream of 422 (this adds a lot of flatwater, but it also adds a couple of neat rapids and some nice scenery); and Rose Point, not far upstream of 422. Rose Point is an easier putin, but it adds some flatwater and parking is limited.
It can be a fun run in the mid-winter, but be warned: you might find the wrong kind of white water.
Click here to see what I mean.
For those who might have trouble with the Slippery Rock Gorge, especially at high water, check out the
Lower Slippery Rock.