Bike trail recommendations for twin 7yos - central PA area

We're looking for some easy-to-moderate bike trails in central PA that would work for 7-year-olds. Not looking for anything crazy, just something fun where they can actually ride instead of walk their bikes the whole time. We've done the Susquehanna Riverlands trail a couple times but open to exploring new areas.

Any recommendations? We're flexible on distance and can go pretty much any weekend.