If you come in the Rea Road or Johnston entrance, you'll have a few miles of paved path. The 51 entrance has about two miles of unpaved pathway, so you wouldn't want to start there.
Mud is frequently on the boards and parts of the pavement, and even if it's not wet, it's not a smooth surface. Also encountered several broken boards which were dangerous walking.
Never seen anyone on blades....
From the Four Mile Creek Greenway parking lot across Trader's Joe, about 0.9 mile out of total 1.75 mile is paved and the rest is wooden boardwalk.
It is mostly paved but there are also lots of sections that are wooden planks. They are kept in good order and are good for running but may be a little difficult for rollerblades. It's also switches between the two somewhat frequently so it's hard to tell how much mileage you could get just on pavement.
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