This is one of my favorite organized rides - the Skagit Spring Classic, Saturday May 9, starting in Burlington, Wa.
One of the great things about this ride is the variety and the number of different loops you can do -- there are 25, 45, 62 and 100-mile options.
It includes the flats of the Skagit Valley, the beautiful coastline ride up Chuckanut Drive, and riding by the shores of Lake Whatcom and Lake Samish. Not much climbing - one notable hill on Bow Hill Drive, the rest that I recall as easy rollers.
Not sure if I'll do it or not - last year I did the century route, but cut out a portion of it and did about 80 easy miles.