I have been riding the Sammamish River and Burke Gilman trails off an on for years and due to a increasing frequency of encounters with well meaning but a little too casual users of the trail, I'm thinking I should look for an alternative route for my long rides.

I have a routine ride route near my home that gets me a good 25K distance with a mix of descents and climbs that help me build strength. But, what I need is a route that has a low traffic interaction level and can support either an out-n-back or a loop of 50K to 75K or relatively flat riding (can be any mix of hard pack "dirt" trail or paved... My cross bike can deal with either.)

What I'm looking for is a route where I can work on sustaining a 25KPH to 32KPH pace without too much interaction with large families of casual bikers (no a comment on them... just trying to find a route where I won't annoy them and they won't interfere with me)

I've got a great hill route near me that has virtually no traffic and is about 15K, but due to the hills isn't a very good pace training route.