Touring - Need oregon touring suggestions

I am looking to do a bike tour loop leaving from portland or. and arriving back there. Looking for something in the 500 mile range, does anyone know any good bike routes or long trails i should hit up? I am going to be looking to camp every night, and see as little cars as possible.

You can ride down the interstates in Oregon the Columbia gorge is nice there are plants and animals there left over from the ice age. You may want to see mount hood. Bend is the best cycling town I have ever been to if you do travel to the middle of the state be warned it is a desert it is possible to be 100 miles from the nearest place to buy an inner tube. Ashland is a nice town while you can travel down interstate 5 there is no reason to use hwy 99 it follows interstate 5. There is an SR 71 blackbird in Mcminnville. I would do a Portland to the Dalles to Bend to Sisters to Salem to McMinnville to Portland. There are some mountains to cross between Bend and Salem. People have offered me rides I only took one when there was 2 feet of snow in Pendleton.

and see as little cars as possible..
could ride off into the National, State Forests on Logging roads.


On Road, ODOT, has improved the width of the shoulders
on 101, down the Coast.
Hundreds of tourists ride it every summer..

Does it have to be a loop?

If I wanted to avoid cars, I'd head eastwards, perhaps eventually direction Spokane and then take Amtrak back...