The trail is almost completely paved from Columbia to Bainbridge. There is a short section section when you reach Marietta that you can either ride a crushed limestone path or choose a very well patched road. The trail then picks up on little-traveled roads in Marietta before rejoining the paved trail. All riding can be done on road bikes.
I would say it is 95% asphalt. Stretching from Columbia River visitor center to Bainbridge.
It is mainly paved asphalt.
The three miles I walked were paved.
There are short stretches of asphalt and gravel. It is mainly dirt.
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